8.2.4 Tokenization

Implementations must act as if they used the following state machine to tokenize HTML. The state machine must start in the data state. Most states consume a single character, which may have various side-effects, and either switches the state machine to a new state to reconsume the same character, or switches it to a new state to consume the next character, or stays in the same state to consume the next character. Some states have more complicated behavior and can consume several characters before switching to another state. In some cases, the tokenizer state is also changed by the tree construction stage.

The exact behavior of certain states depends on the insertion mode and the stack of open elements. Certain states also use a temporary buffer to track progress.

The output of the tokenization step is a series of zero or more of the following tokens: DOCTYPE, start tag, end tag, comment, character, end-of-file. DOCTYPE tokens have a name, a public identifier, a system identifier, and a force-quirks flag. When a DOCTYPE token is created, its name, public identifier, and system identifier must be marked as missing (which is a distinct state from the empty string), and the force-quirks flag must be set to off (its other state is on). Start and end tag tokens have a tag name, a self-closing flag, and a list of attributes, each of which has a name and a value. When a start or end tag token is created, its self-closing flag must be unset (its other state is that it be set), and its attributes list must be empty. Comment and character tokens have data.

When a token is emitted, it must immediately be handled by the tree construction stage. The tree construction stage can affect the state of the tokenization stage, and can insert additional characters into the stream. (For example, the script element can result in scripts executing and using the dynamic markup insertion APIs to insert characters into the stream being tokenized.)

When a start tag token is emitted with its self-closing flag set, if the flag is not acknowledged when it is processed by the tree construction stage, that is a parse error.

When an end tag token is emitted with attributes, that is a parse error.

When an end tag token is emitted with its self-closing flag set, that is a parse error.

An appropriate end tag token is an end tag token whose tag name matches the tag name of the last start tag to have been emitted from this tokenizer, if any. If no start tag has been emitted from this tokenizer, then no end tag token is appropriate.

Before each step of the tokenizer, the user agent must first check the parser pause flag. If it is true, then the tokenizer must abort the processing of any nested invocations of the tokenizer, yielding control back to the caller.

The tokenizer state machine consists of the states defined in the following subsections.

8.2.4.1 Data state

Consume the next input character:

U+0026 AMPERSAND (&)
Switch to the character reference in data state.
U+003C LESS-THAN SIGN (<)
Switch to the tag open state.
U+0000 NULL
Parse error. Emit the current input character as a character token.
EOF
Emit an end-of-file token.
Anything else
Emit the current input character as a character token.
8.2.4.2 Character reference in data state

Switch to the data state.

Attempt to consume a character reference, with no additional allowed character.

If nothing is returned, emit a U+0026 AMPERSAND character (&) token.

Otherwise, emit the character tokens that were returned.

8.2.4.3 RCDATA state

Consume the next input character:

U+0026 AMPERSAND (&)
Switch to the character reference in RCDATA state.
U+003C LESS-THAN SIGN (<)
Switch to the RCDATA less-than sign state.
U+0000 NULL
Parse error. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Emit an end-of-file token.
Anything else
Emit the current input character as a character token.
8.2.4.4 Character reference in RCDATA state

Switch to the RCDATA state.

Attempt to consume a character reference, with no additional allowed character.

If nothing is returned, emit a U+0026 AMPERSAND character (&) token.

Otherwise, emit the character tokens that were returned.

8.2.4.5 RAWTEXT state

Consume the next input character:

U+003C LESS-THAN SIGN (<)
Switch to the RAWTEXT less-than sign state.
U+0000 NULL
Parse error. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Emit an end-of-file token.
Anything else
Emit the current input character as a character token.
8.2.4.6 Script data state

Consume the next input character:

U+003C LESS-THAN SIGN (<)
Switch to the script data less-than sign state.
U+0000 NULL
Parse error. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Emit an end-of-file token.
Anything else
Emit the current input character as a character token.
8.2.4.7 PLAINTEXT state

Consume the next input character:

U+0000 NULL
Parse error. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Emit an end-of-file token.
Anything else
Emit the current input character as a character token.
8.2.4.8 Tag open state

Consume the next input character:

"!" (U+0021)
Switch to the markup declaration open state.
"/" (U+002F)
Switch to the end tag open state.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new start tag token, set its tag name to the lowercase version of the current input character (add 0x0020 to the character's code point), then switch to the tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Create a new start tag token, set its tag name to the current input character, then switch to the tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
"?" (U+003F)
Parse error. Switch to the bogus comment state.
Anything else
Parse error. Switch to the data state. Emit a U+003C LESS-THAN SIGN character token. Reconsume the current input character.
8.2.4.9 End tag open state

Consume the next input character:

U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new end tag token, set its tag name to the lowercase version of the current input character (add 0x0020 to the character's code point), then switch to the tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Create a new end tag token, set its tag name to the current input character, then switch to the tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+003E GREATER-THAN SIGN (>)
Parse error. Switch to the data state.
EOF
Parse error. Switch to the data state. Emit a U+003C LESS-THAN SIGN character token and a U+002F SOLIDUS character token. Reconsume the EOF character.
Anything else
Parse error. Switch to the bogus comment state.
8.2.4.10 Tag name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the before attribute name state.
"/" (U+002F)
Switch to the self-closing start tag state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current tag token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current tag token's tag name.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current tag token's tag name.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Append the current input character to the current tag token's tag name.
8.2.4.11 RCDATA less-than sign state

Consume the next input character:

"/" (U+002F)
Set the temporary buffer to the empty string. Switch to the RCDATA end tag open state.
Anything else
Switch to the RCDATA state. Emit a U+003C LESS-THAN SIGN character token. Reconsume the current input character.
8.2.4.12 RCDATA end tag open state

Consume the next input character:

U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new end tag token, and set its tag name to the lowercase version of the current input character (add 0x0020 to the character's code point). Append the current input character to the temporary buffer. Finally, switch to the RCDATA end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Create a new end tag token, and set its tag name to the current input character. Append the current input character to the temporary buffer. Finally, switch to the RCDATA end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
Anything else
Switch to the RCDATA state. Emit a U+003C LESS-THAN SIGN character token and a U+002F SOLIDUS character token. Reconsume the current input character.
8.2.4.13 RCDATA end tag name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
If the current end tag token is an appropriate end tag token, then switch to the before attribute name state. Otherwise, treat it as per the "anything else" entry below.
"/" (U+002F)
If the current end tag token is an appropriate end tag token, then switch to the self-closing start tag state. Otherwise, treat it as per the "anything else" entry below.
U+003E GREATER-THAN SIGN (>)
If the current end tag token is an appropriate end tag token, then switch to the data state and emit the current tag token. Otherwise, treat it as per the "anything else" entry below.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current tag token's tag name. Append the current input character to the temporary buffer.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Append the current input character to the current tag token's tag name. Append the current input character to the temporary buffer.
Anything else
Switch to the RCDATA state. Emit a U+003C LESS-THAN SIGN character token, a U+002F SOLIDUS character token, and a character token for each of the characters in the temporary buffer (in the order they were added to the buffer). Reconsume the current input character.
8.2.4.14 RAWTEXT less-than sign state

Consume the next input character:

"/" (U+002F)
Set the temporary buffer to the empty string. Switch to the RAWTEXT end tag open state.
Anything else
Switch to the RAWTEXT state. Emit a U+003C LESS-THAN SIGN character token. Reconsume the current input character.
8.2.4.15 RAWTEXT end tag open state

Consume the next input character:

U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new end tag token, and set its tag name to the lowercase version of the current input character (add 0x0020 to the character's code point). Append the current input character to the temporary buffer. Finally, switch to the RAWTEXT end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Create a new end tag token, and set its tag name to the current input character. Append the current input character to the temporary buffer. Finally, switch to the RAWTEXT end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
Anything else
Switch to the RAWTEXT state. Emit a U+003C LESS-THAN SIGN character token and a U+002F SOLIDUS character token. Reconsume the current input character.
8.2.4.16 RAWTEXT end tag name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
If the current end tag token is an appropriate end tag token, then switch to the before attribute name state. Otherwise, treat it as per the "anything else" entry below.
"/" (U+002F)
If the current end tag token is an appropriate end tag token, then switch to the self-closing start tag state. Otherwise, treat it as per the "anything else" entry below.
U+003E GREATER-THAN SIGN (>)
If the current end tag token is an appropriate end tag token, then switch to the data state and emit the current tag token. Otherwise, treat it as per the "anything else" entry below.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current tag token's tag name. Append the current input character to the temporary buffer.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Append the current input character to the current tag token's tag name. Append the current input character to the temporary buffer.
Anything else
Switch to the RAWTEXT state. Emit a U+003C LESS-THAN SIGN character token, a U+002F SOLIDUS character token, and a character token for each of the characters in the temporary buffer (in the order they were added to the buffer). Reconsume the current input character.
8.2.4.17 Script data less-than sign state

Consume the next input character:

"/" (U+002F)
Set the temporary buffer to the empty string. Switch to the script data end tag open state.
"!" (U+0021)
Switch to the script data escape start state. Emit a U+003C LESS-THAN SIGN character token and a U+0021 EXCLAMATION MARK character token.
Anything else
Switch to the script data state. Emit a U+003C LESS-THAN SIGN character token. Reconsume the current input character.
8.2.4.18 Script data end tag open state

Consume the next input character:

U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new end tag token, and set its tag name to the lowercase version of the current input character (add 0x0020 to the character's code point). Append the current input character to the temporary buffer. Finally, switch to the script data end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Create a new end tag token, and set its tag name to the current input character. Append the current input character to the temporary buffer. Finally, switch to the script data end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
Anything else
Switch to the script data state. Emit a U+003C LESS-THAN SIGN character token and a U+002F SOLIDUS character token. Reconsume the current input character.
8.2.4.19 Script data end tag name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
If the current end tag token is an appropriate end tag token, then switch to the before attribute name state. Otherwise, treat it as per the "anything else" entry below.
"/" (U+002F)
If the current end tag token is an appropriate end tag token, then switch to the self-closing start tag state. Otherwise, treat it as per the "anything else" entry below.
U+003E GREATER-THAN SIGN (>)
If the current end tag token is an appropriate end tag token, then switch to the data state and emit the current tag token. Otherwise, treat it as per the "anything else" entry below.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current tag token's tag name. Append the current input character to the temporary buffer.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Append the current input character to the current tag token's tag name. Append the current input character to the temporary buffer.
Anything else
Switch to the script data state. Emit a U+003C LESS-THAN SIGN character token, a U+002F SOLIDUS character token, and a character token for each of the characters in the temporary buffer (in the order they were added to the buffer). Reconsume the current input character.
8.2.4.20 Script data escape start state

Consume the next input character:

"-" (U+002D)
Switch to the script data escape start dash state. Emit a U+002D HYPHEN-MINUS character token.
Anything else
Switch to the script data state. Reconsume the current input character.
8.2.4.21 Script data escape start dash state

Consume the next input character:

"-" (U+002D)
Switch to the script data escaped dash dash state. Emit a U+002D HYPHEN-MINUS character token.
Anything else
Switch to the script data state. Reconsume the current input character.
8.2.4.22 Script data escaped state

Consume the next input character:

"-" (U+002D)
Switch to the script data escaped dash state. Emit a U+002D HYPHEN-MINUS character token.
U+003C LESS-THAN SIGN (<)
Switch to the script data escaped less-than sign state.
U+0000 NULL
Parse error. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Switch to the data state. Parse error. Reconsume the EOF character.
Anything else
Emit the current input character as a character token.
8.2.4.23 Script data escaped dash state

Consume the next input character:

"-" (U+002D)
Switch to the script data escaped dash dash state. Emit a U+002D HYPHEN-MINUS character token.
U+003C LESS-THAN SIGN (<)
Switch to the script data escaped less-than sign state.
U+0000 NULL
Parse error. Switch to the script data escaped state. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Switch to the script data escaped state. Emit the current input character as a character token.
8.2.4.24 Script data escaped dash dash state

Consume the next input character:

"-" (U+002D)
Emit a U+002D HYPHEN-MINUS character token.
U+003C LESS-THAN SIGN (<)
Switch to the script data escaped less-than sign state.
U+003E GREATER-THAN SIGN (>)
Switch to the script data state. Emit a U+003E GREATER-THAN SIGN character token.
U+0000 NULL
Parse error. Switch to the script data escaped state. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Switch to the script data escaped state. Emit the current input character as a character token.
8.2.4.25 Script data escaped less-than sign state

Consume the next input character:

"/" (U+002F)
Set the temporary buffer to the empty string. Switch to the script data escaped end tag open state.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Set the temporary buffer to the empty string. Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the temporary buffer. Switch to the script data double escape start state. Emit a U+003C LESS-THAN SIGN character token and the current input character as a character token.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Set the temporary buffer to the empty string. Append the current input character to the temporary buffer. Switch to the script data double escape start state. Emit a U+003C LESS-THAN SIGN character token and the current input character as a character token.
Anything else
Switch to the script data escaped state. Emit a U+003C LESS-THAN SIGN character token. Reconsume the current input character.
8.2.4.26 Script data escaped end tag open state

Consume the next input character:

U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new end tag token, and set its tag name to the lowercase version of the current input character (add 0x0020 to the character's code point). Append the current input character to the temporary buffer. Finally, switch to the script data escaped end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Create a new end tag token, and set its tag name to the current input character. Append the current input character to the temporary buffer. Finally, switch to the script data escaped end tag name state. (Don't emit the token yet; further details will be filled in before it is emitted.)
Anything else
Switch to the script data escaped state. Emit a U+003C LESS-THAN SIGN character token and a U+002F SOLIDUS character token. Reconsume the current input character.
8.2.4.27 Script data escaped end tag name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
If the current end tag token is an appropriate end tag token, then switch to the before attribute name state. Otherwise, treat it as per the "anything else" entry below.
"/" (U+002F)
If the current end tag token is an appropriate end tag token, then switch to the self-closing start tag state. Otherwise, treat it as per the "anything else" entry below.
U+003E GREATER-THAN SIGN (>)
If the current end tag token is an appropriate end tag token, then switch to the data state and emit the current tag token. Otherwise, treat it as per the "anything else" entry below.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current tag token's tag name. Append the current input character to the temporary buffer.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Append the current input character to the current tag token's tag name. Append the current input character to the temporary buffer.
Anything else
Switch to the script data escaped state. Emit a U+003C LESS-THAN SIGN character token, a U+002F SOLIDUS character token, and a character token for each of the characters in the temporary buffer (in the order they were added to the buffer). Reconsume the current input character.
8.2.4.28 Script data double escape start state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
"/" (U+002F)
U+003E GREATER-THAN SIGN (>)
If the temporary buffer is the string "script", then switch to the script data double escaped state. Otherwise, switch to the script data escaped state. Emit the current input character as a character token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the temporary buffer. Emit the current input character as a character token.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Append the current input character to the temporary buffer. Emit the current input character as a character token.
Anything else
Switch to the script data escaped state. Reconsume the current input character.
8.2.4.29 Script data double escaped state

Consume the next input character:

"-" (U+002D)
Switch to the script data double escaped dash state. Emit a U+002D HYPHEN-MINUS character token.
U+003C LESS-THAN SIGN (<)
Switch to the script data double escaped less-than sign state. Emit a U+003C LESS-THAN SIGN character token.
U+0000 NULL
Parse error. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Emit the current input character as a character token.
8.2.4.30 Script data double escaped dash state

Consume the next input character:

"-" (U+002D)
Switch to the script data double escaped dash dash state. Emit a U+002D HYPHEN-MINUS character token.
U+003C LESS-THAN SIGN (<)
Switch to the script data double escaped less-than sign state. Emit a U+003C LESS-THAN SIGN character token.
U+0000 NULL
Parse error. Switch to the script data double escaped state. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Switch to the script data double escaped state. Emit the current input character as a character token.
8.2.4.31 Script data double escaped dash dash state

Consume the next input character:

"-" (U+002D)
Emit a U+002D HYPHEN-MINUS character token.
U+003C LESS-THAN SIGN (<)
Switch to the script data double escaped less-than sign state. Emit a U+003C LESS-THAN SIGN character token.
U+003E GREATER-THAN SIGN (>)
Switch to the script data state. Emit a U+003E GREATER-THAN SIGN character token.
U+0000 NULL
Parse error. Switch to the script data double escaped state. Emit a U+FFFD REPLACEMENT CHARACTER character token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Switch to the script data double escaped state. Emit the current input character as a character token.
8.2.4.32 Script data double escaped less-than sign state

Consume the next input character:

"/" (U+002F)
Set the temporary buffer to the empty string. Switch to the script data double escape end state. Emit a U+002F SOLIDUS character token.
Anything else
Switch to the script data double escaped state. Reconsume the current input character.
8.2.4.33 Script data double escape end state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
"/" (U+002F)
U+003E GREATER-THAN SIGN (>)
If the temporary buffer is the string "script", then switch to the script data escaped state. Otherwise, switch to the script data double escaped state. Emit the current input character as a character token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the temporary buffer. Emit the current input character as a character token.
U+0061 LATIN SMALL LETTER A through to U+007A LATIN SMALL LETTER Z
Append the current input character to the temporary buffer. Emit the current input character as a character token.
Anything else
Switch to the script data double escaped state. Reconsume the current input character.
8.2.4.34 Before attribute name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
"/" (U+002F)
Switch to the self-closing start tag state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current tag token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Start a new attribute in the current tag token. Set that attribute's name to the lowercase version of the current input character (add 0x0020 to the character's code point), and its value to the empty string. Switch to the attribute name state.
U+0000 NULL
Parse error. Start a new attribute in the current tag token. Set that attribute's name to a U+FFFD REPLACEMENT CHARACTER character, and its value to the empty string. Switch to the attribute name state.
U+0022 QUOTATION MARK (")
"'" (U+0027)
U+003C LESS-THAN SIGN (<)
"=" (U+003D)
Parse error. Treat it as per the "anything else" entry below.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Start a new attribute in the current tag token. Set that attribute's name to the current input character, and its value to the empty string. Switch to the attribute name state.
8.2.4.35 Attribute name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the after attribute name state.
"/" (U+002F)
Switch to the self-closing start tag state.
"=" (U+003D)
Switch to the before attribute value state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current tag token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current attribute's name.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current attribute's name.
U+0022 QUOTATION MARK (")
"'" (U+0027)
U+003C LESS-THAN SIGN (<)
Parse error. Treat it as per the "anything else" entry below.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Append the current input character to the current attribute's name.

When the user agent leaves the attribute name state (and before emitting the tag token, if appropriate), the complete attribute's name must be compared to the other attributes on the same token; if there is already an attribute on the token with the exact same name, then this is a parse error and the new attribute must be dropped, along with the value that gets associated with it (if any).

8.2.4.36 After attribute name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
"/" (U+002F)
Switch to the self-closing start tag state.
"=" (U+003D)
Switch to the before attribute value state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current tag token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Start a new attribute in the current tag token. Set that attribute's name to the lowercase version of the current input character (add 0x0020 to the character's code point), and its value to the empty string. Switch to the attribute name state.
U+0000 NULL
Parse error. Start a new attribute in the current tag token. Set that attribute's name to a U+FFFD REPLACEMENT CHARACTER character, and its value to the empty string. Switch to the attribute name state.
U+0022 QUOTATION MARK (")
"'" (U+0027)
U+003C LESS-THAN SIGN (<)
Parse error. Treat it as per the "anything else" entry below.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Start a new attribute in the current tag token. Set that attribute's name to the current input character, and its value to the empty string. Switch to the attribute name state.
8.2.4.37 Before attribute value state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+0022 QUOTATION MARK (")
Switch to the attribute value (double-quoted) state.
U+0026 AMPERSAND (&)
Switch to the attribute value (unquoted) state. Reconsume the current input character.
"'" (U+0027)
Switch to the attribute value (single-quoted) state.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current attribute's value. Switch to the attribute value (unquoted) state.
U+003E GREATER-THAN SIGN (>)
Parse error. Switch to the data state. Emit the current tag token.
U+003C LESS-THAN SIGN (<)
"=" (U+003D)
"`" (U+0060)
Parse error. Treat it as per the "anything else" entry below.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Append the current input character to the current attribute's value. Switch to the attribute value (unquoted) state.
8.2.4.38 Attribute value (double-quoted) state

Consume the next input character:

U+0022 QUOTATION MARK (")
Switch to the after attribute value (quoted) state.
U+0026 AMPERSAND (&)
Switch to the character reference in attribute value state, with the additional allowed character being U+0022 QUOTATION MARK (").
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current attribute's value.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Append the current input character to the current attribute's value.
8.2.4.39 Attribute value (single-quoted) state

Consume the next input character:

"'" (U+0027)
Switch to the after attribute value (quoted) state.
U+0026 AMPERSAND (&)
Switch to the character reference in attribute value state, with the additional allowed character being "'" (U+0027).
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current attribute's value.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Append the current input character to the current attribute's value.
8.2.4.40 Attribute value (unquoted) state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the before attribute name state.
U+0026 AMPERSAND (&)
Switch to the character reference in attribute value state, with the additional allowed character being U+003E GREATER-THAN SIGN (>).
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current tag token.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current attribute's value.
U+0022 QUOTATION MARK (")
"'" (U+0027)
U+003C LESS-THAN SIGN (<)
"=" (U+003D)
"`" (U+0060)
Parse error. Treat it as per the "anything else" entry below.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Append the current input character to the current attribute's value.
8.2.4.41 Character reference in attribute value state

Attempt to consume a character reference.

If nothing is returned, append a U+0026 AMPERSAND character (&) to the current attribute's value.

Otherwise, append the returned character tokens to the current attribute's value.

Finally, switch back to the attribute value state that switched into this state.

8.2.4.42 After attribute value (quoted) state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the before attribute name state.
"/" (U+002F)
Switch to the self-closing start tag state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current tag token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Parse error. Switch to the before attribute name state. Reconsume the character.
8.2.4.43 Self-closing start tag state

Consume the next input character:

U+003E GREATER-THAN SIGN (>)
Set the self-closing flag of the current tag token. Switch to the data state. Emit the current tag token.
EOF
Parse error. Switch to the data state. Reconsume the EOF character.
Anything else
Parse error. Switch to the before attribute name state. Reconsume the character.
8.2.4.44 Bogus comment state

Consume every character up to and including the first U+003E GREATER-THAN SIGN character (>) or the end of the file (EOF), whichever comes first. Emit a comment token whose data is the concatenation of all the characters starting from and including the character that caused the state machine to switch into the bogus comment state, up to and including the character immediately before the last consumed character (i.e. up to the character just before the U+003E or EOF character), but with any U+0000 NULL characters replaced by U+FFFD REPLACEMENT CHARACTER characters. (If the comment was started by the end of the file (EOF), the token is empty. Similarly, the token is empty if it was generated by the string "<!>".)

Switch to the data state.

If the end of the file was reached, reconsume the EOF character.

8.2.4.45 Markup declaration open state

If the next two characters are both "-" (U+002D) characters, consume those two characters, create a comment token whose data is the empty string, and switch to the comment start state.

Otherwise, if the next seven characters are an ASCII case-insensitive match for the word "DOCTYPE", then consume those characters and switch to the DOCTYPE state.

Otherwise, if there is a current node and it is not an element in the HTML namespace and the next seven characters are a case-sensitive match for the string "[CDATA[" (the five uppercase letters "CDATA" with a U+005B LEFT SQUARE BRACKET character before and after), then consume those characters and switch to the CDATA section state.

Otherwise, this is a parse error. Switch to the bogus comment state. The next character that is consumed, if any, is the first character that will be in the comment.

8.2.4.46 Comment start state

Consume the next input character:

"-" (U+002D)
Switch to the comment start dash state.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the comment token's data. Switch to the comment state.
U+003E GREATER-THAN SIGN (>)
Parse error. Switch to the data state. Emit the comment token.
EOF
Parse error. Switch to the data state. Emit the comment token. Reconsume the EOF character.
Anything else
Append the current input character to the comment token's data. Switch to the comment state.
8.2.4.47 Comment start dash state

Consume the next input character:

"-" (U+002D)
Switch to the comment end state
U+0000 NULL
Parse error. Append a "-" (U+002D) character and a U+FFFD REPLACEMENT CHARACTER character to the comment token's data. Switch to the comment state.
U+003E GREATER-THAN SIGN (>)
Parse error. Switch to the data state. Emit the comment token.
EOF
Parse error. Switch to the data state. Emit the comment token. Reconsume the EOF character.
Anything else
Append a "-" (U+002D) character and the current input character to the comment token's data. Switch to the comment state.
8.2.4.48 Comment state

Consume the next input character:

"-" (U+002D)
Switch to the comment end dash state
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the comment token's data.
EOF
Parse error. Switch to the data state. Emit the comment token. Reconsume the EOF character.
Anything else
Append the current input character to the comment token's data.
8.2.4.49 Comment end dash state

Consume the next input character:

"-" (U+002D)
Switch to the comment end state
U+0000 NULL
Parse error. Append a "-" (U+002D) character and a U+FFFD REPLACEMENT CHARACTER character to the comment token's data. Switch to the comment state.
EOF
Parse error. Switch to the data state. Emit the comment token. Reconsume the EOF character.
Anything else
Append a "-" (U+002D) character and the current input character to the comment token's data. Switch to the comment state.
8.2.4.50 Comment end state

Consume the next input character:

U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the comment token.
U+0000 NULL
Parse error. Append two "-" (U+002D) characters and a U+FFFD REPLACEMENT CHARACTER character to the comment token's data. Switch to the comment state.
"!" (U+0021)
Parse error. Switch to the comment end bang state.
"-" (U+002D)
Parse error. Append a "-" (U+002D) character to the comment token's data.
EOF
Parse error. Switch to the data state. Emit the comment token. Reconsume the EOF character.
Anything else
Parse error. Append two "-" (U+002D) characters and the current input character to the comment token's data. Switch to the comment state.
8.2.4.51 Comment end bang state

Consume the next input character:

"-" (U+002D)
Append two "-" (U+002D) characters and a "!" (U+0021) character to the comment token's data. Switch to the comment end dash state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the comment token.
U+0000 NULL
Parse error. Append two "-" (U+002D) characters, a "!" (U+0021) character, and a U+FFFD REPLACEMENT CHARACTER character to the comment token's data. Switch to the comment state.
EOF
Parse error. Switch to the data state. Emit the comment token. Reconsume the EOF character.
Anything else
Append two "-" (U+002D) characters, a "!" (U+0021) character, and the current input character to the comment token's data. Switch to the comment state.
8.2.4.52 DOCTYPE state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the before DOCTYPE name state.
EOF
Parse error. Switch to the data state. Create a new DOCTYPE token. Set its force-quirks flag to on. Emit the token. Reconsume the EOF character.
Anything else
Parse error. Switch to the before DOCTYPE name state. Reconsume the character.
8.2.4.53 Before DOCTYPE name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Create a new DOCTYPE token. Set the token's name to the lowercase version of the current input character (add 0x0020 to the character's code point). Switch to the DOCTYPE name state.
U+0000 NULL
Parse error. Create a new DOCTYPE token. Set the token's name to a U+FFFD REPLACEMENT CHARACTER character. Switch to the DOCTYPE name state.
U+003E GREATER-THAN SIGN (>)
Parse error. Create a new DOCTYPE token. Set its force-quirks flag to on. Switch to the data state. Emit the token.
EOF
Parse error. Switch to the data state. Create a new DOCTYPE token. Set its force-quirks flag to on. Emit the token. Reconsume the EOF character.
Anything else
Create a new DOCTYPE token. Set the token's name to the current input character. Switch to the DOCTYPE name state.
8.2.4.54 DOCTYPE name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the after DOCTYPE name state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current DOCTYPE token.
U+0041 LATIN CAPITAL LETTER A through to U+005A LATIN CAPITAL LETTER Z
Append the lowercase version of the current input character (add 0x0020 to the character's code point) to the current DOCTYPE token's name.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current DOCTYPE token's name.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Append the current input character to the current DOCTYPE token's name.
8.2.4.55 After DOCTYPE name state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else

If the six characters starting from the current input character are an ASCII case-insensitive match for the word "PUBLIC", then consume those characters and switch to the after DOCTYPE public keyword state.

Otherwise, if the six characters starting from the current input character are an ASCII case-insensitive match for the word "SYSTEM", then consume those characters and switch to the after DOCTYPE system keyword state.

Otherwise, this is a parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.

8.2.4.56 After DOCTYPE public keyword state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the before DOCTYPE public identifier state.
U+0022 QUOTATION MARK (")
Parse error. Set the DOCTYPE token's public identifier to the empty string (not missing), then switch to the DOCTYPE public identifier (double-quoted) state.
"'" (U+0027)
Parse error. Set the DOCTYPE token's public identifier to the empty string (not missing), then switch to the DOCTYPE public identifier (single-quoted) state.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.
8.2.4.57 Before DOCTYPE public identifier state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+0022 QUOTATION MARK (")
Set the DOCTYPE token's public identifier to the empty string (not missing), then switch to the DOCTYPE public identifier (double-quoted) state.
"'" (U+0027)
Set the DOCTYPE token's public identifier to the empty string (not missing), then switch to the DOCTYPE public identifier (single-quoted) state.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.
8.2.4.58 DOCTYPE public identifier (double-quoted) state

Consume the next input character:

U+0022 QUOTATION MARK (")
Switch to the after DOCTYPE public identifier state.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current DOCTYPE token's public identifier.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Append the current input character to the current DOCTYPE token's public identifier.
8.2.4.59 DOCTYPE public identifier (single-quoted) state

Consume the next input character:

"'" (U+0027)
Switch to the after DOCTYPE public identifier state.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current DOCTYPE token's public identifier.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Append the current input character to the current DOCTYPE token's public identifier.
8.2.4.60 After DOCTYPE public identifier state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the between DOCTYPE public and system identifiers state.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current DOCTYPE token.
U+0022 QUOTATION MARK (")
Parse error. Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (double-quoted) state.
"'" (U+0027)
Parse error. Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (single-quoted) state.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.
8.2.4.61 Between DOCTYPE public and system identifiers state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current DOCTYPE token.
U+0022 QUOTATION MARK (")
Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (double-quoted) state.
"'" (U+0027)
Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (single-quoted) state.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.
8.2.4.62 After DOCTYPE system keyword state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Switch to the before DOCTYPE system identifier state.
U+0022 QUOTATION MARK (")
Parse error. Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (double-quoted) state.
"'" (U+0027)
Parse error. Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (single-quoted) state.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.
8.2.4.63 Before DOCTYPE system identifier state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+0022 QUOTATION MARK (")
Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (double-quoted) state.
"'" (U+0027)
Set the DOCTYPE token's system identifier to the empty string (not missing), then switch to the DOCTYPE system identifier (single-quoted) state.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the bogus DOCTYPE state.
8.2.4.64 DOCTYPE system identifier (double-quoted) state

Consume the next input character:

U+0022 QUOTATION MARK (")
Switch to the after DOCTYPE system identifier state.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current DOCTYPE token's system identifier.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Append the current input character to the current DOCTYPE token's system identifier.
8.2.4.65 DOCTYPE system identifier (single-quoted) state

Consume the next input character:

"'" (U+0027)
Switch to the after DOCTYPE system identifier state.
U+0000 NULL
Parse error. Append a U+FFFD REPLACEMENT CHARACTER character to the current DOCTYPE token's system identifier.
U+003E GREATER-THAN SIGN (>)
Parse error. Set the DOCTYPE token's force-quirks flag to on. Switch to the data state. Emit that DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Append the current input character to the current DOCTYPE token's system identifier.
8.2.4.66 After DOCTYPE system identifier state

Consume the next input character:

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
Ignore the character.
U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the current DOCTYPE token.
EOF
Parse error. Switch to the data state. Set the DOCTYPE token's force-quirks flag to on. Emit that DOCTYPE token. Reconsume the EOF character.
Anything else
Parse error. Switch to the bogus DOCTYPE state. (This does not set the DOCTYPE token's force-quirks flag to on.)
8.2.4.67 Bogus DOCTYPE state

Consume the next input character:

U+003E GREATER-THAN SIGN (>)
Switch to the data state. Emit the DOCTYPE token.
EOF
Switch to the data state. Emit the DOCTYPE token. Reconsume the EOF character.
Anything else
Ignore the character.
8.2.4.68 CDATA section state

Switch to the data state.

Consume every character up to the next occurrence of the three character sequence U+005D RIGHT SQUARE BRACKET U+005D RIGHT SQUARE BRACKET U+003E GREATER-THAN SIGN (]]>), or the end of the file (EOF), whichever comes first. Emit a series of character tokens consisting of all the characters consumed except the matching three character sequence at the end (if one was found before the end of the file).

If the end of the file was reached, reconsume the EOF character.

8.2.4.69 Tokenizing character references

This section defines how to consume a character reference. This definition is used when parsing character references in text and in attributes.

The behavior depends on the identity of the next character (the one immediately after the U+0026 AMPERSAND character):

"tab" (U+0009)
"LF" (U+000A)
"FF" (U+000C)
U+0020 SPACE
U+003C LESS-THAN SIGN
U+0026 AMPERSAND
EOF
The additional allowed character, if there is one
Not a character reference. No characters are consumed, and nothing is returned. (This is not an error, either.)
"#" (U+0023)

Consume the U+0023 NUMBER SIGN.

The behavior further depends on the character after the U+0023 NUMBER SIGN:

U+0078 LATIN SMALL LETTER X
U+0058 LATIN CAPITAL LETTER X

Consume the X.

Follow the steps below, but using the range of characters ASCII digits, U+0061 LATIN SMALL LETTER A to U+0066 LATIN SMALL LETTER F, and U+0041 LATIN CAPITAL LETTER A to U+0046 LATIN CAPITAL LETTER F (in other words, 0-9, A-F, a-f).

When it comes to interpreting the number, interpret it as a hexadecimal number.

Anything else

Follow the steps below, but using the range of characters ASCII digits.

When it comes to interpreting the number, interpret it as a decimal number.

Consume as many characters as match the range of characters given above.

If no characters match the range, then don't consume any characters (and unconsume the U+0023 NUMBER SIGN character and, if appropriate, the X character). This is a parse error; nothing is returned.

Otherwise, if the next character is a U+003B SEMICOLON, consume that too. If it isn't, there is a parse error.

If one or more characters match the range, then take them all and interpret the string of characters as a number (either hexadecimal or decimal as appropriate).

If that number is one of the numbers in the first column of the following table, then this is a parse error. Find the row with that number in the first column, and return a character token for the Unicode character given in the second column of that row.

Number Unicode character
0x00 U+FFFD REPLACEMENT CHARACTER
0x0D U+000D CARRIAGE RETURN (CR)
0x80 U+20AC EURO SIGN (€)
0x81 U+0081 <control>
0x82 U+201A SINGLE LOW-9 QUOTATION MARK (‚)
0x83 U+0192 LATIN SMALL LETTER F WITH HOOK (ƒ)
0x84 U+201E DOUBLE LOW-9 QUOTATION MARK („)
0x85 U+2026 HORIZONTAL ELLIPSIS (…)
0x86 U+2020 DAGGER (†)
0x87 U+2021 DOUBLE DAGGER (‡)
0x88 U+02C6 MODIFIER LETTER CIRCUMFLEX ACCENT (ˆ)
0x89 U+2030 PER MILLE SIGN (‰)
0x8A U+0160 LATIN CAPITAL LETTER S WITH CARON (Š)
0x8B U+2039 SINGLE LEFT-POINTING ANGLE QUOTATION MARK (‹)
0x8C U+0152 LATIN CAPITAL LIGATURE OE (Œ)
0x8D U+008D <control>
0x8E U+017D LATIN CAPITAL LETTER Z WITH CARON (Ž)
0x8F U+008F <control>
0x90 U+0090 <control>
0x91 U+2018 LEFT SINGLE QUOTATION MARK (‘)
0x92 U+2019 RIGHT SINGLE QUOTATION MARK (’)
0x93 U+201C LEFT DOUBLE QUOTATION MARK (“)
0x94 U+201D RIGHT DOUBLE QUOTATION MARK (”)
0x95 U+2022 BULLET (•)
0x96 U+2013 EN DASH (–)
0x97 U+2014 EM DASH (—)
0x98 U+02DC SMALL TILDE (˜)
0x99 U+2122 TRADE MARK SIGN (™)
0x9A U+0161 LATIN SMALL LETTER S WITH CARON (š)
0x9B U+203A SINGLE RIGHT-POINTING ANGLE QUOTATION MARK (›)
0x9C U+0153 LATIN SMALL LIGATURE OE (œ)
0x9D U+009D <control>
0x9E U+017E LATIN SMALL LETTER Z WITH CARON (ž)
0x9F U+0178 LATIN CAPITAL LETTER Y WITH DIAERESIS (Ÿ)

Otherwise, if the number is in the range 0xD800 to 0xDFFF or is greater than 0x10FFFF, then this is a parse error. Return a U+FFFD REPLACEMENT CHARACTER.

Otherwise, return a character token for the Unicode character whose code point is that number. Additionally, if the number is in the range 0x0001 to 0x0008, 0x000E to 0x001F, 0x007F to 0x009F, 0xFDD0 to 0xFDEF, or is one of 0x000B, 0xFFFE, 0xFFFF, 0x1FFFE, 0x1FFFF, 0x2FFFE, 0x2FFFF, 0x3FFFE, 0x3FFFF, 0x4FFFE, 0x4FFFF, 0x5FFFE, 0x5FFFF, 0x6FFFE, 0x6FFFF, 0x7FFFE, 0x7FFFF, 0x8FFFE, 0x8FFFF, 0x9FFFE, 0x9FFFF, 0xAFFFE, 0xAFFFF, 0xBFFFE, 0xBFFFF, 0xCFFFE, 0xCFFFF, 0xDFFFE, 0xDFFFF, 0xEFFFE, 0xEFFFF, 0xFFFFE, 0xFFFFF, 0x10FFFE, or 0x10FFFF, then this is a parse error.

Anything else

Consume the maximum number of characters possible, with the consumed characters matching one of the identifiers in the first column of the named character references table (in a case-sensitive manner).

If no match can be made, then no characters are consumed, and nothing is returned. In this case, if the characters after the U+0026 AMPERSAND character (&) consist of a sequence of one or more characters in the range ASCII digits, lowercase ASCII letters, and uppercase ASCII letters, followed by a ";" (U+003B) character, then this is a parse error.

If the character reference is being consumed as part of an attribute, and the last character matched is not a ";" (U+003B) character, and the next character is either a "=" (U+003D) character or in the range ASCII digits, uppercase ASCII letters, or lowercase ASCII letters, then, for historical reasons, all the characters that were matched after the U+0026 AMPERSAND character (&) must be unconsumed, and nothing is returned.

Otherwise, a character reference is parsed. If the last character matched is not a ";" (U+003B) character, there is a parse error.

Return one or two character tokens for the character(s) corresponding to the character reference name (as given by the second column of the named character references table).

If the markup contains (not in an attribute) the string I'm &notit; I tell you, the character reference is parsed as "not", as in, I'm ¬it; I tell you (and this is a parse error). But if the markup was I'm &notin; I tell you, the character reference would be parsed as "notin;", resulting in I'm ∉ I tell you (and no parse error).

8.2.5 Tree construction

The input to the tree construction stage is a sequence of tokens from the tokenization stage. The tree construction stage is associated with a DOM Document object when a parser is created. The "output" of this stage consists of dynamically modifying or extending that document's DOM tree.

This specification does not define when an interactive user agent has to render the Document so that it is available to the user, or when it has to begin accepting user input.


As each token is emitted from the tokenizer, the user agent must follow the appropriate steps from the following list:

If there is no current node
If the current node is an element in the HTML namespace
If the current node is a MathML text integration point and the token is a start tag whose tag name is neither "mglyph" nor "malignmark"
If the current node is a MathML text integration point and the token is a character token
If the current node is an annotation-xml element in the MathML namespace and the token is a start tag whose tag name is "svg"
If the current node is an HTML integration point and the token is a start tag
If the current node is an HTML integration point and the token is a character token
If the token is an end-of-file token
Process the token according to the rules given in the section corresponding to the current insertion mode in HTML content.
Otherwise
Process the token according to the rules given in the section for parsing tokens in foreign content.

When the specification says that a user agent is to act as if a token had been seen, it means that the user agent is to follow the appropriate steps from the above list.

The current node is a MathML text integration point if it is one of the following elements:

The current node is an HTML integration point if it is one of the following elements:


When the steps below require the UA to insert a character into a node, if that node has a child immediately before where the character is to be inserted, and that child is a Text node, then the character must be appended to that Text node; otherwise, a new Text node whose data is just that character must be inserted in the appropriate place.

Here are some sample inputs to the parser and the corresponding number of Text nodes that they result in, assuming a user agent that executes scripts.

Input Number of Text nodes
A<script>
var script = document.getElementsByTagName('script')[0];
document.body.removeChild(script);
</script>B
One Text node in the document, containing "AB".
A<script>
var text = document.createTextNode('B');
document.body.appendChild(text);
</script>C
Three Text nodes; "A" before the script, the script's contents, and "BC" after the script (the parser appends to the Text node created by the script).
A<script>
var text = document.getElementsByTagName('script')[0].firstChild;
text.data = 'B';
document.body.appendChild(text);
</script>C
Two adjacent Text nodes in the document, containing "A" and "BC".
A<table>B<tr>C</tr>D</table>
One Text node before the table, containing "ABCD". (This is caused by foster parenting.)
A<table><tr> B</tr> C</table>
One Text node before the table, containing "A B C" (A-space-B-space-C). (This is caused by foster parenting.)
A<table><tr> B</tr> </em>C</table>
One Text node before the table, containing "A BC" (A-space-B-C), and one Text node inside the table (as a child of a tbody) with a single space character. (Space characters separated from non-space characters by non-character tokens are not affected by foster parenting, even if those other tokens then get ignored.)

DOM mutation events and mutation observers must not fire for changes caused by the UA parsing the document. (Conceptually, the parser is not mutating the DOM, it is constructing it.) This includes the parsing of any content inserted using document.write() and document.writeln() calls. [DOMEVENTS]

Not all of the tag names mentioned below are conformant tag names in this specification; many are included to handle legacy content. They still form part of the algorithm that implementations are required to implement to claim conformance.

The algorithm described below places no limit on the depth of the DOM tree generated, or on the length of tag names, attribute names, attribute values, Text nodes, etc. While implementors are encouraged to avoid arbitrary limits, it is recognized that practical concerns will likely force user agents to impose nesting depth constraints.

8.2.5.1 Creating and inserting elements

When the steps below require the UA to create an element for a token in a particular namespace, the UA must create a node implementing the interface appropriate for the element type corresponding to the tag name of the token in the given namespace (as given in the specification that defines that element, e.g. for an a element in the HTML namespace, this specification defines it to be the HTMLAnchorElement interface), with the tag name being the name of that element, with the node being in the given namespace, and with the attributes on the node being those given in the given token.

The interface appropriate for an element in the HTML namespace that is not defined in this specification (or other applicable specifications) is HTMLUnknownElement. Elements in other namespaces whose interface is not defined by that namespace's specification must use the interface Element.

When a resettable element is created in this manner, its reset algorithm must be invoked once the attributes are set. (This initializes the element's value and checkedness based on the element's attributes.)


When the steps below require the UA to insert an HTML element for a token, the UA must first create an element for the token in the HTML namespace, and then append this node to the current node, and push it onto the stack of open elements so that it is the new current node.

The steps below may also require that the UA insert an HTML element in a particular place, in which case the UA must follow the same steps except that it must insert or append the new node in the location specified instead of appending it to the current node. (This happens in particular during the parsing of tables with invalid content.)

If an element created by the insert an HTML element algorithm is a form-associated element, and the form element pointer is not null, and the newly created element doesn't have a form attribute, the user agent must associate the newly created element with the form element pointed to by the form element pointer when the element is inserted, instead of running the reset the form owner algorithm.


When the steps below require the UA to insert a foreign element for a token, the UA must first create an element for the token in the given namespace, and then append this node to the current node, and push it onto the stack of open elements so that it is the new current node. If the newly created element has an xmlns attribute in the XMLNS namespace whose value is not exactly the same as the element's namespace, that is a parse error. Similarly, if the newly created element has an xmlns:xlink attribute in the XMLNS namespace whose value is not the XLink Namespace, that is a parse error.

When the steps below require the user agent to adjust MathML attributes for a token, then, if the token has an attribute named definitionurl, change its name to definitionURL (note the case difference).

When the steps below require the user agent to adjust SVG attributes for a token, then, for each attribute on the token whose attribute name is one of the ones in the first column of the following table, change the attribute's name to the name given in the corresponding cell in the second column. (This fixes the case of SVG attributes that are not all lowercase.)

Attribute name on token Attribute name on element
attributename attributeName
attributetype attributeType
basefrequency baseFrequency
baseprofile baseProfile
calcmode calcMode
clippathunits clipPathUnits
contentscripttype contentScriptType
contentstyletype contentStyleType
diffuseconstant diffuseConstant
edgemode edgeMode
externalresourcesrequired externalResourcesRequired
filterres filterRes
filterunits filterUnits
glyphref glyphRef
gradienttransform gradientTransform
gradientunits gradientUnits
kernelmatrix kernelMatrix
kernelunitlength kernelUnitLength
keypoints keyPoints
keysplines keySplines
keytimes keyTimes
lengthadjust lengthAdjust
limitingconeangle limitingConeAngle
markerheight markerHeight
markerunits markerUnits
markerwidth markerWidth
maskcontentunits maskContentUnits
maskunits maskUnits
numoctaves numOctaves
pathlength pathLength
patterncontentunits patternContentUnits
patterntransform patternTransform
patternunits patternUnits
pointsatx pointsAtX
pointsaty pointsAtY
pointsatz pointsAtZ
preservealpha preserveAlpha
preserveaspectratio preserveAspectRatio
primitiveunits primitiveUnits
refx refX
refy refY
repeatcount repeatCount
repeatdur repeatDur
requiredextensions requiredExtensions
requiredfeatures requiredFeatures
specularconstant specularConstant
specularexponent specularExponent
spreadmethod spreadMethod
startoffset startOffset
stddeviation stdDeviation
stitchtiles stitchTiles
surfacescale surfaceScale
systemlanguage systemLanguage
tablevalues tableValues
targetx targetX
targety targetY
textlength textLength
viewbox viewBox
viewtarget viewTarget
xchannelselector xChannelSelector
ychannelselector yChannelSelector
zoomandpan zoomAndPan

When the steps below require the user agent to adjust foreign attributes for a token, then, if any of the attributes on the token match the strings given in the first column of the following table, let the attribute be a namespaced attribute, with the prefix being the string given in the corresponding cell in the second column, the local name being the string given in the corresponding cell in the third column, and the namespace being the namespace given in the corresponding cell in the fourth column. (This fixes the use of namespaced attributes, in particular lang attributes in the XML namespace.)

Attribute name Prefix Local name Namespace
xlink:actuate xlink actuate XLink namespace
xlink:arcrole xlink arcrole XLink namespace
xlink:href xlink href XLink namespace
xlink:role xlink role XLink namespace
xlink:show xlink show XLink namespace
xlink:title xlink title XLink namespace
xlink:type xlink type XLink namespace
xml:base xml base XML namespace
xml:lang xml lang XML namespace
xml:space xml space XML namespace
xmlns (none) xmlns XMLNS namespace
xmlns:xlink xmlns xlink XMLNS namespace

The generic raw text element parsing algorithm and the generic RCDATA element parsing algorithm consist of the following steps. These algorithms are always invoked in response to a start tag token.

  1. Insert an HTML element for the token.

  2. If the algorithm that was invoked is the generic raw text element parsing algorithm, switch the tokenizer to the RAWTEXT state; otherwise the algorithm invoked was the generic RCDATA element parsing algorithm, switch the tokenizer to the RCDATA state.

  3. Let the original insertion mode be the current insertion mode.

  4. Then, switch the insertion mode to "text".

8.2.5.2 Closing elements that have implied end tags

When the steps below require the UA to generate implied end tags, then, while the current node is a dd element, a dt element, an li element, an option element, an optgroup element, a p element, an rp element, or an rt element, the UA must pop the current node off the stack of open elements.

If a step requires the UA to generate implied end tags but lists an element to exclude from the process, then the UA must perform the above steps as if that element was not in the above list.

8.2.5.3 Foster parenting

Foster parenting happens when content is misnested in tables.

When a node node is to be foster parented, the node node must be inserted into the foster parent element.

This typically happens as part of the insert an HTML element algorithm above: when that algorithm would normally insert the newly created node into the current node, it gets inserted into the foster parent element instead.

The foster parent element is the parent element of the last table element in the stack of open elements, if there is a table element and it has such a parent element.

It might have no parent or some other kind parent if a script manipulated the DOM after the element was inserted by the parser.

If there is no table element in the stack of open elements (fragment case), then the foster parent element is the first element in the stack of open elements (the html element). Otherwise, if there is a table element in the stack of open elements, but the last table element in the stack of open elements has no parent, or its parent node is not an element, then the foster parent element is the element before the last table element in the stack of open elements.

If the foster parent element is the parent element of the last table element in the stack of open elements, then node must be inserted into the foster parent element, immediately before the last table element in the stack of open elements; otherwise, node must be appended to the foster parent element.

8.2.5.4 The rules for parsing tokens in HTML content
8.2.5.4.1 The "initial" insertion mode

When the user agent is to apply the rules for the "initial" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Ignore the token.

A comment token

Append a Comment node to the Document object with the data attribute set to the data given in the comment token.

A DOCTYPE token

If the DOCTYPE token's name is not a case-sensitive match for the string "html", or the token's public identifier is not missing, or the token's system identifier is neither missing nor a case-sensitive match for the string "about:legacy-compat", and none of the sets of conditions in the following list are matched, then there is a parse error.

  • The DOCTYPE token's name is a case-sensitive match for the string "html", the token's public identifier is the case-sensitive string "-//W3C//DTD HTML 4.0//EN", and the token's system identifier is either missing or the case-sensitive string "http://www.w3.org/TR/REC-html40/strict.dtd".
  • The DOCTYPE token's name is a case-sensitive match for the string "html", the token's public identifier is the case-sensitive string "-//W3C//DTD HTML 4.01//EN", and the token's system identifier is either missing or the case-sensitive string "http://www.w3.org/TR/html4/strict.dtd".
  • The DOCTYPE token's name is a case-sensitive match for the string "html", the token's public identifier is the case-sensitive string "-//W3C//DTD XHTML 1.0 Strict//EN", and the token's system identifier is the case-sensitive string "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd".
  • The DOCTYPE token's name is a case-sensitive match for the string "html", the token's public identifier is the case-sensitive string "-//W3C//DTD XHTML 1.1//EN", and the token's system identifier is the case-sensitive string "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd".

Conformance checkers may, based on the values (including presence or lack thereof) of the DOCTYPE token's name, public identifier, or system identifier, switch to a conformance checking mode for another language (e.g. based on the DOCTYPE token a conformance checker could recognize that the document is an HTML4-era document, and defer to an HTML4 conformance checker.)

Append a DocumentType node to the Document node, with the name attribute set to the name given in the DOCTYPE token, or the empty string if the name was missing; the publicId attribute set to the public identifier given in the DOCTYPE token, or the empty string if the public identifier was missing; the systemId attribute set to the system identifier given in the DOCTYPE token, or the empty string if the system identifier was missing; and the other attributes specific to DocumentType objects set to null and empty lists as appropriate. Associate the DocumentType node with the Document object so that it is returned as the value of the doctype attribute of the Document object.

Then, if the DOCTYPE token matches one of the conditions in the following list, then set the Document to quirks mode:

  • The force-quirks flag is set to on.
  • The name is set to anything other than "html" (compared case-sensitively).
  • The public identifier starts with: "+//Silmaril//dtd html Pro v0r11 19970101//"
  • The public identifier starts with: "-//AdvaSoft Ltd//DTD HTML 3.0 asWedit + extensions//"
  • The public identifier starts with: "-//AS//DTD HTML 3.0 asWedit + extensions//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.0 Level 1//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.0 Level 2//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.0 Strict Level 1//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.0 Strict Level 2//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.0 Strict//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.0//"
  • The public identifier starts with: "-//IETF//DTD HTML 2.1E//"
  • The public identifier starts with: "-//IETF//DTD HTML 3.0//"
  • The public identifier starts with: "-//IETF//DTD HTML 3.2 Final//"
  • The public identifier starts with: "-//IETF//DTD HTML 3.2//"
  • The public identifier starts with: "-//IETF//DTD HTML 3//"
  • The public identifier starts with: "-//IETF//DTD HTML Level 0//"
  • The public identifier starts with: "-//IETF//DTD HTML Level 1//"
  • The public identifier starts with: "-//IETF//DTD HTML Level 2//"
  • The public identifier starts with: "-//IETF//DTD HTML Level 3//"
  • The public identifier starts with: "-//IETF//DTD HTML Strict Level 0//"
  • The public identifier starts with: "-//IETF//DTD HTML Strict Level 1//"
  • The public identifier starts with: "-//IETF//DTD HTML Strict Level 2//"
  • The public identifier starts with: "-//IETF//DTD HTML Strict Level 3//"
  • The public identifier starts with: "-//IETF//DTD HTML Strict//"
  • The public identifier starts with: "-//IETF//DTD HTML//"
  • The public identifier starts with: "-//Metrius//DTD Metrius Presentational//"
  • The public identifier starts with: "-//Microsoft//DTD Internet Explorer 2.0 HTML Strict//"
  • The public identifier starts with: "-//Microsoft//DTD Internet Explorer 2.0 HTML//"
  • The public identifier starts with: "-//Microsoft//DTD Internet Explorer 2.0 Tables//"
  • The public identifier starts with: "-//Microsoft//DTD Internet Explorer 3.0 HTML Strict//"
  • The public identifier starts with: "-//Microsoft//DTD Internet Explorer 3.0 HTML//"
  • The public identifier starts with: "-//Microsoft//DTD Internet Explorer 3.0 Tables//"
  • The public identifier starts with: "-//Netscape Comm. Corp.//DTD HTML//"
  • The public identifier starts with: "-//Netscape Comm. Corp.//DTD Strict HTML//"
  • The public identifier starts with: "-//O'Reilly and Associates//DTD HTML 2.0//"
  • The public identifier starts with: "-//O'Reilly and Associates//DTD HTML Extended 1.0//"
  • The public identifier starts with: "-//O'Reilly and Associates//DTD HTML Extended Relaxed 1.0//"
  • The public identifier starts with: "-//SoftQuad Software//DTD HoTMetaL PRO 6.0::19990601::extensions to HTML 4.0//"
  • The public identifier starts with: "-//SoftQuad//DTD HoTMetaL PRO 4.0::19971010::extensions to HTML 4.0//"
  • The public identifier starts with: "-//Spyglass//DTD HTML 2.0 Extended//"
  • The public identifier starts with: "-//SQ//DTD HTML 2.0 HoTMetaL + extensions//"
  • The public identifier starts with: "-//Sun Microsystems Corp.//DTD HotJava HTML//"
  • The public identifier starts with: "-//Sun Microsystems Corp.//DTD HotJava Strict HTML//"
  • The public identifier starts with: "-//W3C//DTD HTML 3 1995-03-24//"
  • The public identifier starts with: "-//W3C//DTD HTML 3.2 Draft//"
  • The public identifier starts with: "-//W3C//DTD HTML 3.2 Final//"
  • The public identifier starts with: "-//W3C//DTD HTML 3.2//"
  • The public identifier starts with: "-//W3C//DTD HTML 3.2S Draft//"
  • The public identifier starts with: "-//W3C//DTD HTML 4.0 Frameset//"
  • The public identifier starts with: "-//W3C//DTD HTML 4.0 Transitional//"
  • The public identifier starts with: "-//W3C//DTD HTML Experimental 19960712//"
  • The public identifier starts with: "-//W3C//DTD HTML Experimental 970421//"
  • The public identifier starts with: "-//W3C//DTD W3 HTML//"
  • The public identifier starts with: "-//W3O//DTD W3 HTML 3.0//"
  • The public identifier is set to: "-//W3O//DTD W3 HTML Strict 3.0//EN//"
  • The public identifier starts with: "-//WebTechs//DTD Mozilla HTML 2.0//"
  • The public identifier starts with: "-//WebTechs//DTD Mozilla HTML//"
  • The public identifier is set to: "-/W3C/DTD HTML 4.0 Transitional/EN"
  • The public identifier is set to: "HTML"
  • The system identifier is set to: "http://www.ibm.com/data/dtd/v11/ibmxhtml1-transitional.dtd"
  • The system identifier is missing and the public identifier starts with: "-//W3C//DTD HTML 4.01 Frameset//"
  • The system identifier is missing and the public identifier starts with: "-//W3C//DTD HTML 4.01 Transitional//"

Otherwise, if the DOCTYPE token matches one of the conditions in the following list, then set the Document to limited-quirks mode:

  • The public identifier starts with: "-//W3C//DTD XHTML 1.0 Frameset//"
  • The public identifier starts with: "-//W3C//DTD XHTML 1.0 Transitional//"
  • The system identifier is not missing and the public identifier starts with: "-//W3C//DTD HTML 4.01 Frameset//"
  • The system identifier is not missing and the public identifier starts with: "-//W3C//DTD HTML 4.01 Transitional//"

The system identifier and public identifier strings must be compared to the values given in the lists above in an ASCII case-insensitive manner. A system identifier whose value is the empty string is not considered missing for the purposes of the conditions above.

Then, switch the insertion mode to "before html".

Anything else

If the document is not an iframe srcdoc document, then this is a parse error; set the Document to quirks mode.

In any case, switch the insertion mode to "before html", then reprocess the current token.

8.2.5.4.2 The "before html" insertion mode

When the user agent is to apply the rules for the "before html" insertion mode, the user agent must handle the token as follows:

A DOCTYPE token

Parse error. Ignore the token.

A comment token

Append a Comment node to the Document object with the data attribute set to the data given in the comment token.

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Ignore the token.

A start tag whose tag name is "html"

Create an element for the token in the HTML namespace. Append it to the Document object. Put this element in the stack of open elements.

If the Document is being loaded as part of navigation of a browsing context, then: if the newly created element has a manifest attribute whose value is not the empty string, then resolve the value of that attribute to an absolute URL, relative to the newly created element, and if that is successful, run the application cache selection algorithm with the resulting absolute URL with any <fragment> component removed; otherwise, if there is no such attribute, or its value is the empty string, or resolving its value fails, run the application cache selection algorithm with no manifest. The algorithm must be passed the Document object.

Switch the insertion mode to "before head".

An end tag whose tag name is one of: "head", "body", "html", "br"

Act as described in the "anything else" entry below.

Any other end tag

Parse error. Ignore the token.

Anything else

Create an html element. Append it to the Document object. Put this element in the stack of open elements.

If the Document is being loaded as part of navigation of a browsing context, then: run the application cache selection algorithm with no manifest, passing it the Document object.

Switch the insertion mode to "before head", then reprocess the current token.

The root element can end up being removed from the Document object, e.g. by scripts; nothing in particular happens in such cases, content continues being appended to the nodes as described in the next section.

8.2.5.4.3 The "before head" insertion mode

When the user agent is to apply the rules for the "before head" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Ignore the token.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

A start tag whose tag name is "head"

Insert an HTML element for the token.

Set the head element pointer to the newly created head element.

Switch the insertion mode to "in head".

An end tag whose tag name is one of: "head", "body", "html", "br"

Act as if a start tag token with the tag name "head" and no attributes had been seen, then reprocess the current token.

Any other end tag

Parse error. Ignore the token.

Anything else

Act as if a start tag token with the tag name "head" and no attributes had been seen, then reprocess the current token.

8.2.5.4.4 The "in head" insertion mode

When the user agent is to apply the rules for the "in head" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Insert the character into the current node.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

A start tag whose tag name is one of: "base", "basefont", "bgsound", "command", "link"

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

A start tag whose tag name is "meta"

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

If the element has a charset attribute, and its value is either a supported ASCII-compatible character encoding or a UTF-16 encoding, and the confidence is currently tentative, then change the encoding to the encoding given by the value of the charset attribute.

Otherwise, if the element has an http-equiv attribute whose value is an ASCII case-insensitive match for the string "Content-Type", and the element has a content attribute, and applying the algorithm for extracting a character encoding from a meta element to that attribute's value returns a supported ASCII-compatible character encoding or a UTF-16 encoding, and the confidence is currently tentative, then change the encoding to the extracted encoding.

A start tag whose tag name is "title"

Follow the generic RCDATA element parsing algorithm.

A start tag whose tag name is "noscript", if the scripting flag is enabled
A start tag whose tag name is one of: "noframes", "style"

Follow the generic raw text element parsing algorithm.

A start tag whose tag name is "noscript", if the scripting flag is disabled

Insert an HTML element for the token.

Switch the insertion mode to "in head noscript".

A start tag whose tag name is "script"

Run these steps:

  1. Create an element for the token in the HTML namespace.

  2. Mark the element as being "parser-inserted" and unset the element's "force-async" flag.

    This ensures that, if the script is external, any document.write() calls in the script will execute in-line, instead of blowing the document away, as would happen in most other cases. It also prevents the script from executing until the end tag is seen.

  3. If the parser was originally created for the HTML fragment parsing algorithm, then mark the script element as "already started". (fragment case)

  4. Append the new element to the current node and push it onto the stack of open elements.

  5. Switch the tokenizer to the script data state.

  6. Let the original insertion mode be the current insertion mode.

  7. Switch the insertion mode to "text".

An end tag whose tag name is "head"

Pop the current node (which will be the head element) off the stack of open elements.

Switch the insertion mode to "after head".

An end tag whose tag name is one of: "body", "html", "br"

Act as described in the "anything else" entry below.

A start tag whose tag name is "head"
Any other end tag

Parse error. Ignore the token.

Anything else

Act as if an end tag token with the tag name "head" had been seen, and reprocess the current token.

8.2.5.4.5 The "in head noscript" insertion mode

When the user agent is to apply the rules for the "in head noscript" insertion mode, the user agent must handle the token as follows:

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

An end tag whose tag name is "noscript"

Pop the current node (which will be a noscript element) from the stack of open elements; the new current node will be a head element.

Switch the insertion mode to "in head".

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE
A comment token
A start tag whose tag name is one of: "basefont", "bgsound", "link", "meta", "noframes", "style"

Process the token using the rules for the "in head" insertion mode.

An end tag whose tag name is "br"

Act as described in the "anything else" entry below.

A start tag whose tag name is one of: "head", "noscript"
Any other end tag

Parse error. Ignore the token.

Anything else

Parse error. Act as if an end tag with the tag name "noscript" had been seen and reprocess the current token.

8.2.5.4.6 The "after head" insertion mode

When the user agent is to apply the rules for the "after head" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Insert the character into the current node.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

A start tag whose tag name is "body"

Insert an HTML element for the token.

Set the frameset-ok flag to "not ok".

Switch the insertion mode to "in body".

A start tag whose tag name is "frameset"

Insert an HTML element for the token.

Switch the insertion mode to "in frameset".

A start tag token whose tag name is one of: "base", "basefont", "bgsound", "link", "meta", "noframes", "script", "style", "title"

Parse error.

Push the node pointed to by the head element pointer onto the stack of open elements.

Process the token using the rules for the "in head" insertion mode.

Remove the node pointed to by the head element pointer from the stack of open elements.

The head element pointer cannot be null at this point.

An end tag whose tag name is one of: "body", "html", "br"

Act as described in the "anything else" entry below.

A start tag whose tag name is "head"
Any other end tag

Parse error. Ignore the token.

Anything else

Act as if a start tag token with the tag name "body" and no attributes had been seen, then set the frameset-ok flag back to "ok", and then reprocess the current token.

8.2.5.4.7 The "in body" insertion mode

When the user agent is to apply the rules for the "in body" insertion mode, the user agent must handle the token as follows:

A character token that is U+0000 NULL

Parse error. Ignore the token.

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Reconstruct the active formatting elements, if any.

Insert the token's character into the current node.

Any other character token

Reconstruct the active formatting elements, if any.

Insert the token's character into the current node.

Set the frameset-ok flag to "not ok".

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Parse error. For each attribute on the token, check to see if the attribute is already present on the top element of the stack of open elements. If it is not, add the attribute and its corresponding value to that element.

A start tag token whose tag name is one of: "base", "basefont", "bgsound", "command", "link", "meta", "noframes", "script", "style", "title"

Process the token using the rules for the "in head" insertion mode.

A start tag whose tag name is "body"

Parse error.

If the second element on the stack of open elements is not a body element, or, if the stack of open elements has only one node on it, then ignore the token. (fragment case)

Otherwise, set the frameset-ok flag to "not ok"; then, for each attribute on the token, check to see if the attribute is already present on the body element (the second element) on the stack of open elements, and if it is not, add the attribute and its corresponding value to that element.

A start tag whose tag name is "frameset"

Parse error.

If the second element on the stack of open elements is not a body element, or, if the stack of open elements has only one node on it, then ignore the token. (fragment case)

If the frameset-ok flag is set to "not ok", ignore the token.

Otherwise, run the following steps:

  1. Remove the second element on the stack of open elements from its parent node, if it has one.

  2. Pop all the nodes from the bottom of the stack of open elements, from the current node up to, but not including, the root html element.

  3. Insert an HTML element for the token.

  4. Switch the insertion mode to "in frameset".

An end-of-file token

If there is a node in the stack of open elements that is not either a dd element, a dt element, an li element, a p element, a tbody element, a td element, a tfoot element, a th element, a thead element, a tr element, the body element, or the html element, then this is a parse error.

Stop parsing.

An end tag whose tag name is "body"

If the stack of open elements does not have a body element in scope, this is a parse error; ignore the token.

Otherwise, if there is a node in the stack of open elements that is not either a dd element, a dt element, an li element, an optgroup element, an option element, a p element, an rp element, an rt element, a tbody element, a td element, a tfoot element, a th element, a thead element, a tr element, the body element, or the html element, then this is a parse error.

Switch the insertion mode to "after body".

An end tag whose tag name is "html"

Act as if an end tag with tag name "body" had been seen, then, if that token wasn't ignored, reprocess the current token.

A start tag whose tag name is one of: "address", "article", "aside", "blockquote", "center", "details", "dialog", "dir", "div", "dl", "fieldset", "figcaption", "figure", "footer", "header", "hgroup", "menu", "nav", "ol", "p", "section", "summary", "ul"

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Insert an HTML element for the token.

A start tag whose tag name is one of: "h1", "h2", "h3", "h4", "h5", "h6"

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

If the current node is an element whose tag name is one of "h1", "h2", "h3", "h4", "h5", or "h6", then this is a parse error; pop the current node off the stack of open elements.

Insert an HTML element for the token.

A start tag whose tag name is one of: "pre", "listing"

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Insert an HTML element for the token.

If the next token is a "LF" (U+000A) character token, then ignore that token and move on to the next one. (Newlines at the start of pre blocks are ignored as an authoring convenience.)

Set the frameset-ok flag to "not ok".

A start tag whose tag name is "form"

If the form element pointer is not null, then this is a parse error; ignore the token.

Otherwise:

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Insert an HTML element for the token, and set the form element pointer to point to the element created.

A start tag whose tag name is "li"

Run these steps:

  1. Set the frameset-ok flag to "not ok".

  2. Initialize node to be the current node (the bottommost node of the stack).

  3. Loop: If node is an li element, then act as if an end tag with the tag name "li" had been seen, then jump to the last step.

  4. If node is in the special category, but is not an address, div, or p element, then jump to the last step.

  5. Otherwise, set node to the previous entry in the stack of open elements and return to the step labeled loop.

  6. This is the last step.

    If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

    Finally, insert an HTML element for the token.

A start tag whose tag name is one of: "dd", "dt"

Run these steps:

  1. Set the frameset-ok flag to "not ok".

  2. Initialize node to be the current node (the bottommost node of the stack).

  3. Loop: If node is a dd or dt element, then act as if an end tag with the same tag name as node had been seen, then jump to the last step.

  4. If node is in the special category, but is not an address, div, or p element, then jump to the last step.

  5. Otherwise, set node to the previous entry in the stack of open elements and return to the step labeled loop.

  6. This is the last step.

    If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

    Finally, insert an HTML element for the token.

A start tag whose tag name is "plaintext"

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Insert an HTML element for the token.

Switch the tokenizer to the PLAINTEXT state.

Once a start tag with the tag name "plaintext" has been seen, that will be the last token ever seen other than character tokens (and the end-of-file token), because there is no way to switch out of the PLAINTEXT state.

A start tag whose tag name is "button"

If the stack of open elements has a button element in scope, then this is a parse error; act as if an end tag with the tag name "button" had been seen, then reprocess the token.

Otherwise:

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token.

Set the frameset-ok flag to "not ok".

An end tag whose tag name is one of: "address", "article", "aside", "blockquote", "button", "center", "details", "dialog", "dir", "div", "dl", "fieldset", "figcaption", "figure", "footer", "header", "hgroup", "listing", "menu", "nav", "ol", "pre", "section", "summary", "ul"

If the stack of open elements does not have an element in scope with the same tag name as that of the token, then this is a parse error; ignore the token.

Otherwise, run these steps:

  1. Generate implied end tags.

  2. If the current node is not an element with the same tag name as that of the token, then this is a parse error.

  3. Pop elements from the stack of open elements until an element with the same tag name as the token has been popped from the stack.

An end tag whose tag name is "form"

Let node be the element that the form element pointer is set to.

Set the form element pointer to null.

If node is null or the stack of open elements does not have node in scope, then this is a parse error; ignore the token.

Otherwise, run these steps:

  1. Generate implied end tags.

  2. If the current node is not node, then this is a parse error.

  3. Remove node from the stack of open elements.

An end tag whose tag name is "p"

If the stack of open elements does not have an element in button scope with the same tag name as that of the token, then this is a parse error; act as if a start tag with the tag name "p" had been seen, then reprocess the current token.

Otherwise, run these steps:

  1. Generate implied end tags, except for elements with the same tag name as the token.

  2. If the current node is not an element with the same tag name as that of the token, then this is a parse error.

  3. Pop elements from the stack of open elements until an element with the same tag name as the token has been popped from the stack.

An end tag whose tag name is "li"

If the stack of open elements does not have an element in list item scope with the same tag name as that of the token, then this is a parse error; ignore the token.

Otherwise, run these steps:

  1. Generate implied end tags, except for elements with the same tag name as the token.

  2. If the current node is not an element with the same tag name as that of the token, then this is a parse error.

  3. Pop elements from the stack of open elements until an element with the same tag name as the token has been popped from the stack.

An end tag whose tag name is one of: "dd", "dt"

If the stack of open elements does not have an element in scope with the same tag name as that of the token, then this is a parse error; ignore the token.

Otherwise, run these steps:

  1. Generate implied end tags, except for elements with the same tag name as the token.

  2. If the current node is not an element with the same tag name as that of the token, then this is a parse error.

  3. Pop elements from the stack of open elements until an element with the same tag name as the token has been popped from the stack.

An end tag whose tag name is one of: "h1", "h2", "h3", "h4", "h5", "h6"

If the stack of open elements does not have an element in scope whose tag name is one of "h1", "h2", "h3", "h4", "h5", or "h6", then this is a parse error; ignore the token.

Otherwise, run these steps:

  1. Generate implied end tags.

  2. If the current node is not an element with the same tag name as that of the token, then this is a parse error.

  3. Pop elements from the stack of open elements until an element whose tag name is one of "h1", "h2", "h3", "h4", "h5", or "h6" has been popped from the stack.

An end tag whose tag name is "sarcasm"

Take a deep breath, then act as described in the "any other end tag" entry below.

A start tag whose tag name is "a"

If the list of active formatting elements contains an element whose tag name is "a" between the end of the list and the last marker on the list (or the start of the list if there is no marker on the list), then this is a parse error; act as if an end tag with the tag name "a" had been seen, then remove that element from the list of active formatting elements and the stack of open elements if the end tag didn't already remove it (it might not have if the element is not in table scope).

In the non-conforming stream <a href="a">a<table><a href="b">b</table>x, the first a element would be closed upon seeing the second one, and the "x" character would be inside a link to "b", not to "a". This is despite the fact that the outer a element is not in table scope (meaning that a regular </a> end tag at the start of the table wouldn't close the outer a element). The result is that the two a elements are indirectly nested inside each other — non-conforming markup will often result in non-conforming DOMs when parsed.

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token. Push onto the list of active formatting elements that element.

A start tag whose tag name is one of: "b", "big", "code", "em", "font", "i", "s", "small", "strike", "strong", "tt", "u"

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token. Push onto the list of active formatting elements that element.

A start tag whose tag name is "nobr"

Reconstruct the active formatting elements, if any.

If the stack of open elements has a nobr element in scope, then this is a parse error; act as if an end tag with the tag name "nobr" had been seen, then once again reconstruct the active formatting elements, if any.

Insert an HTML element for the token. Push onto the list of active formatting elements that element.

An end tag whose tag name is one of: "a", "b", "big", "code", "em", "font", "i", "nobr", "s", "small", "strike", "strong", "tt", "u"

Run these steps:

  1. Let outer loop counter be zero.

  2. Outer loop: If outer loop counter is greater than or equal to eight, then abort these steps.

  3. Increment outer loop counter by one.

  4. Let the formatting element be the last element in the list of active formatting elements that:

    • is between the end of the list and the last scope marker in the list, if any, or the start of the list otherwise, and
    • has the same tag name as the token.

    If there is no such node, then abort these steps and instead act as described in the "any other end tag" entry below.

    Otherwise, if there is such a node, but that node is not in the stack of open elements, then this is a parse error; remove the element from the list, and abort these steps.

    Otherwise, if there is such a node, and that node is also in the stack of open elements, but the element is not in scope, then this is a parse error; ignore the token, and abort these steps.

    Otherwise, there is a formatting element and that element is in the stack and is in scope. If the element is not the current node, this is a parse error. In any case, proceed with the algorithm as written in the following steps.

  5. Let the furthest block be the topmost node in the stack of open elements that is lower in the stack than the formatting element, and is an element in the special category. There might not be one.

  6. If there is no furthest block, then the UA must first pop all the nodes from the bottom of the stack of open elements, from the current node up to and including the formatting element, then remove the formatting element from the list of active formatting elements, and finally abort these steps.

  7. Let the common ancestor be the element immediately above the formatting element in the stack of open elements.

  8. Let a bookmark note the position of the formatting element in the list of active formatting elements relative to the elements on either side of it in the list.

  9. Let node and last node be the furthest block. Follow these steps:

    1. Let inner loop counter be zero.

    2. Inner loop: If inner loop counter is greater than or equal to three, then go to the next step in the overall algorithm.

    3. Increment inner loop counter by one.

    4. Let node be the element immediately above node in the stack of open elements, or if node is no longer in the stack of open elements (e.g. because it got removed by the next step), the element that was immediately above node in the stack of open elements before node was removed.
    5. If node is not in the list of active formatting elements, then remove node from the stack of open elements and then go back to the step labeled inner loop.
    6. Otherwise, if node is the formatting element, then go to the next step in the overall algorithm.
    7. Create an element for the token for which the element node was created, replace the entry for node in the list of active formatting elements with an entry for the new element, replace the entry for node in the stack of open elements with an entry for the new element, and let node be the new element.
    8. If last node is the furthest block, then move the aforementioned bookmark to be immediately after the new node in the list of active formatting elements.
    9. Insert last node into node, first removing it from its previous parent node if any.
    10. Let last node be node.
    11. Return to the step labeled inner loop.
  10. If the common ancestor node is a table, tbody, tfoot, thead, or tr element, then, foster parent whatever last node ended up being in the previous step, first removing it from its previous parent node if any.

    Otherwise, append whatever last node ended up being in the previous step to the common ancestor node, first removing it from its previous parent node if any.

  11. Create an element for the token for which the formatting element was created.

  12. Take all of the child nodes of the furthest block and append them to the element created in the last step.

  13. Append that new element to the furthest block.

  14. Remove the formatting element from the list of active formatting elements, and insert the new element into the list of active formatting elements at the position of the aforementioned bookmark.

  15. Remove the formatting element from the stack of open elements, and insert the new element into the stack of open elements immediately below the position of the furthest block in that stack.

  16. Jump back to the step labeled outer loop.

Because of the way this algorithm causes elements to change parents, it has been dubbed the "adoption agency algorithm" (in contrast with other possible algorithms for dealing with misnested content, which included the "incest algorithm", the "secret affair algorithm", and the "Heisenberg algorithm").

A start tag token whose tag name is one of: "applet", "marquee", "object"

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token.

Insert a marker at the end of the list of active formatting elements.

Set the frameset-ok flag to "not ok".

An end tag token whose tag name is one of: "applet", "marquee", "object"

If the stack of open elements does not have an element in scope with the same tag name as that of the token, then this is a parse error; ignore the token.

Otherwise, run these steps:

  1. Generate implied end tags.

  2. If the current node is not an element with the same tag name as that of the token, then this is a parse error.

  3. Pop elements from the stack of open elements until an element with the same tag name as the token has been popped from the stack.

  4. Clear the list of active formatting elements up to the last marker.
A start tag whose tag name is "table"

If the Document is not set to quirks mode, and the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Insert an HTML element for the token.

Set the frameset-ok flag to "not ok".

Switch the insertion mode to "in table".

A start tag whose tag name is one of: "area", "br", "embed", "img", "keygen", "wbr"

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

Set the frameset-ok flag to "not ok".

A start tag whose tag name is "input"

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

If the token does not have an attribute with the name "type", or if it does, but that attribute's value is not an ASCII case-insensitive match for the string "hidden", then: set the frameset-ok flag to "not ok".

A start tag whose tag name is one of: "param", "source", "track"

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

A start tag whose tag name is "hr"

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

Set the frameset-ok flag to "not ok".

A start tag whose tag name is "image"

Parse error. Change the token's tag name to "img" and reprocess it. (Don't ask.)

A start tag whose tag name is "isindex"

Parse error.

If the form element pointer is not null, then ignore the token.

Otherwise:

Acknowledge the token's self-closing flag, if it is set.

Act as if a start tag token with the tag name "form" had been seen.

If the token has an attribute called "action", set the action attribute on the resulting form element to the value of the "action" attribute of the token.

Act as if a start tag token with the tag name "hr" had been seen.

Act as if a start tag token with the tag name "label" had been seen.

Act as if a stream of character tokens had been seen (see below for what they should say).

Act as if a start tag token with the tag name "input" had been seen, with all the attributes from the "isindex" token except "name", "action", and "prompt". Set the name attribute of the resulting input element to the value "isindex".

Act as if a stream of character tokens had been seen (see below for what they should say).

Act as if an end tag token with the tag name "label" had been seen.

Act as if a start tag token with the tag name "hr" had been seen.

Act as if an end tag token with the tag name "form" had been seen.

If the token has an attribute with the name "prompt", then the first stream of characters must be the same string as given in that attribute, and the second stream of characters must be empty. Otherwise, the two streams of character tokens together should, together with the input element, express the equivalent of "This is a searchable index. Enter search keywords: (input field)" in the user's preferred language.

A start tag whose tag name is "textarea"

Run these steps:

  1. Insert an HTML element for the token.

  2. If the next token is a "LF" (U+000A) character token, then ignore that token and move on to the next one. (Newlines at the start of textarea elements are ignored as an authoring convenience.)

  3. Switch the tokenizer to the RCDATA state.

  4. Let the original insertion mode be the current insertion mode.

  5. Set the frameset-ok flag to "not ok".

  6. Switch the insertion mode to "text".

A start tag whose tag name is "xmp"

If the stack of open elements has a p element in button scope, then act as if an end tag with the tag name "p" had been seen.

Reconstruct the active formatting elements, if any.

Set the frameset-ok flag to "not ok".

Follow the generic raw text element parsing algorithm.

A start tag whose tag name is "iframe"

Set the frameset-ok flag to "not ok".

Follow the generic raw text element parsing algorithm.

A start tag whose tag name is "noembed"
A start tag whose tag name is "noscript", if the scripting flag is enabled

Follow the generic raw text element parsing algorithm.

A start tag whose tag name is "select"

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token.

Set the frameset-ok flag to "not ok".

If the insertion mode is one of "in table", "in caption", "in table body", "in row", or "in cell", then switch the insertion mode to "in select in table". Otherwise, switch the insertion mode to "in select".

A start tag whose tag name is one of: "optgroup", "option"

If the current node is an option element, then act as if an end tag with the tag name "option" had been seen.

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token.

A start tag whose tag name is one of: "rp", "rt"

If the stack of open elements has a ruby element in scope, then generate implied end tags. If the current node is not then a ruby element, this is a parse error.

Insert an HTML element for the token.

An end tag whose tag name is "br"

Parse error. Act as if a start tag token with the tag name "br" had been seen. Ignore the end tag token.

A start tag whose tag name is "math"

Reconstruct the active formatting elements, if any.

Adjust MathML attributes for the token. (This fixes the case of MathML attributes that are not all lowercase.)

Adjust foreign attributes for the token. (This fixes the use of namespaced attributes, in particular XLink.)

Insert a foreign element for the token, in the MathML namespace.

If the token has its self-closing flag set, pop the current node off the stack of open elements and acknowledge the token's self-closing flag.

A start tag whose tag name is "svg"

Reconstruct the active formatting elements, if any.

Adjust SVG attributes for the token. (This fixes the case of SVG attributes that are not all lowercase.)

Adjust foreign attributes for the token. (This fixes the use of namespaced attributes, in particular XLink in SVG.)

Insert a foreign element for the token, in the SVG namespace.

If the token has its self-closing flag set, pop the current node off the stack of open elements and acknowledge the token's self-closing flag.

A start tag whose tag name is one of: "caption", "col", "colgroup", "frame", "head", "tbody", "td", "tfoot", "th", "thead", "tr"

Parse error. Ignore the token.

Any other start tag

Reconstruct the active formatting elements, if any.

Insert an HTML element for the token.

This element will be an ordinary element.

Any other end tag

Run these steps:

  1. Initialize node to be the current node (the bottommost node of the stack).

  2. Loop: If node has the same tag name as the token, then:

    1. Generate implied end tags, except for elements with the same tag name as the token.

    2. If the tag name of the end tag token does not match the tag name of the current node, this is a parse error.

    3. Pop all the nodes from the current node up to node, including node, then stop these steps.

  3. Otherwise, if node is in the special category, then this is a parse error; ignore the token, and abort these steps.

  4. Set node to the previous entry in the stack of open elements.

  5. Return to the step labeled loop.

8.2.5.4.8 The "text" insertion mode

When the user agent is to apply the rules for the "text" insertion mode, the user agent must handle the token as follows:

A character token

Insert the token's character into the current node.

This can never be a U+0000 NULL character; the tokenizer converts those to U+FFFD REPLACEMENT CHARACTER characters.

An end-of-file token

Parse error.

If the current node is a script element, mark the script element as "already started".

Pop the current node off the stack of open elements.

Switch the insertion mode to the original insertion mode and reprocess the current token.

An end tag whose tag name is "script"

Provide a stable state.

Let script be the current node (which will be a script element).

Pop the current node off the stack of open elements.

Switch the insertion mode to the original insertion mode.

Let the old insertion point have the same value as the current insertion point. Let the insertion point be just before the next input character.

Increment the parser's script nesting level by one.

Prepare the script. This might cause some script to execute, which might cause new characters to be inserted into the tokenizer, and might cause the tokenizer to output more tokens, resulting in a reentrant invocation of the parser.

Decrement the parser's script nesting level by one. If the parser's script nesting level is zero, then set the parser pause flag to false.

Let the insertion point have the value of the old insertion point. (In other words, restore the insertion point to its previous value. This value might be the "undefined" value.)

At this stage, if there is a pending parsing-blocking script, then:

If the script nesting level is not zero:

Set the parser pause flag to true, and abort the processing of any nested invocations of the tokenizer, yielding control back to the caller. (Tokenization will resume when the caller returns to the "outer" tree construction stage.)

The tree construction stage of this particular parser is being called reentrantly, say from a call to document.write().

Otherwise:

Run these steps:

  1. Let the script be the pending parsing-blocking script. There is no longer a pending parsing-blocking script.

  2. Block the tokenizer for this instance of the HTML parser, such that the event loop will not run tasks that invoke the tokenizer.

  3. If the parser's Document has a style sheet that is blocking scripts or the script's "ready to be parser-executed" flag is not set: spin the event loop until the parser's Document has no style sheet that is blocking scripts and the script's "ready to be parser-executed" flag is set.

  4. Unblock the tokenizer for this instance of the HTML parser, such that tasks that invoke the tokenizer can again be run.

  5. Let the insertion point be just before the next input character.

  6. Increment the parser's script nesting level by one (it should be zero before this step, so this sets it to one).

  7. Execute the script.

  8. Decrement the parser's script nesting level by one. If the parser's script nesting level is zero (which it always should be at this point), then set the parser pause flag to false.

  9. Let the insertion point be undefined again.

  10. If there is once again a pending parsing-blocking script, then repeat these steps from step 1.

Any other end tag

Pop the current node off the stack of open elements.

Switch the insertion mode to the original insertion mode.

8.2.5.4.9 The "in table" insertion mode

When the user agent is to apply the rules for the "in table" insertion mode, the user agent must handle the token as follows:

A character token, if the current node is table, tbody, tfoot, thead, or tr element

Let the pending table character tokens be an empty list of tokens.

Let the original insertion mode be the current insertion mode.

Switch the insertion mode to "in table text" and reprocess the token.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "caption"

Clear the stack back to a table context. (See below.)

Insert a marker at the end of the list of active formatting elements.

Insert an HTML element for the token, then switch the insertion mode to "in caption".

A start tag whose tag name is "colgroup"

Clear the stack back to a table context. (See below.)

Insert an HTML element for the token, then switch the insertion mode to "in column group".

A start tag whose tag name is "col"

Act as if a start tag token with the tag name "colgroup" had been seen, then reprocess the current token.

A start tag whose tag name is one of: "tbody", "tfoot", "thead"

Clear the stack back to a table context. (See below.)

Insert an HTML element for the token, then switch the insertion mode to "in table body".

A start tag whose tag name is one of: "td", "th", "tr"

Act as if a start tag token with the tag name "tbody" had been seen, then reprocess the current token.

A start tag whose tag name is "table"

Parse error. Act as if an end tag token with the tag name "table" had been seen, then, if that token wasn't ignored, reprocess the current token.

The fake end tag token here can only be ignored in the fragment case.

An end tag whose tag name is "table"

If the stack of open elements does not have an element in table scope with the same tag name as the token, this is a parse error. Ignore the token. (fragment case)

Otherwise:

Pop elements from this stack until a table element has been popped from the stack.

Reset the insertion mode appropriately.

An end tag whose tag name is one of: "body", "caption", "col", "colgroup", "html", "tbody", "td", "tfoot", "th", "thead", "tr"

Parse error. Ignore the token.

A start tag whose tag name is one of: "style", "script"

Process the token using the rules for the "in head" insertion mode.

A start tag whose tag name is "input"

If the token does not have an attribute with the name "type", or if it does, but that attribute's value is not an ASCII case-insensitive match for the string "hidden", then: act as described in the "anything else" entry below.

Otherwise:

Parse error.

Insert an HTML element for the token.

Pop that input element off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

A start tag whose tag name is "form"

Parse error.

If the form element pointer is not null, ignore the token.

Otherwise:

Insert an HTML element for the token, and set the form element pointer to point to the element created.

Pop that form element off the stack of open elements.

An end-of-file token

If the current node is not the root html element, then this is a parse error.

The current node can only be the root html element in the fragment case.

Stop parsing.

Anything else

Parse error. Process the token using the rules for the "in body" insertion mode, except that whenever a node would be inserted into the current node when the current node is a table, tbody, tfoot, thead, or tr element, then it must instead be foster parented.

When the steps above require the UA to clear the stack back to a table context, it means that the UA must, while the current node is not a table element or an html element, pop elements from the stack of open elements.

The current node being an html element after this process is a fragment case.

8.2.5.4.10 The "in table text" insertion mode

When the user agent is to apply the rules for the "in table text" insertion mode, the user agent must handle the token as follows:

A character token that is U+0000 NULL

Parse error. Ignore the token.

Any other character token

Append the character token to the pending table character tokens list.

Anything else

If any of the tokens in the pending table character tokens list are character tokens that are not space characters, then reprocess the character tokens in the pending table character tokens list using the rules given in the "anything else" entry in the "in table" insertion mode.

Otherwise, insert the characters given by the pending table character tokens list into the current node.

Switch the insertion mode to the original insertion mode and reprocess the token.

8.2.5.4.11 The "in caption" insertion mode

When the user agent is to apply the rules for the "in caption" insertion mode, the user agent must handle the token as follows:

An end tag whose tag name is "caption"

If the stack of open elements does not have an element in table scope with the same tag name as the token, this is a parse error. Ignore the token. (fragment case)

Otherwise:

Generate implied end tags.

Now, if the current node is not a caption element, then this is a parse error.

Pop elements from this stack until a caption element has been popped from the stack.

Clear the list of active formatting elements up to the last marker.

Switch the insertion mode to "in table".

A start tag whose tag name is one of: "caption", "col", "colgroup", "tbody", "td", "tfoot", "th", "thead", "tr"
An end tag whose tag name is "table"

Parse error. Act as if an end tag with the tag name "caption" had been seen, then, if that token wasn't ignored, reprocess the current token.

The fake end tag token here can only be ignored in the fragment case.

An end tag whose tag name is one of: "body", "col", "colgroup", "html", "tbody", "td", "tfoot", "th", "thead", "tr"

Parse error. Ignore the token.

Anything else

Process the token using the rules for the "in body" insertion mode.

8.2.5.4.12 The "in column group" insertion mode

When the user agent is to apply the rules for the "in column group" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Insert the character into the current node.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

A start tag whose tag name is "col"

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

An end tag whose tag name is "colgroup"

If the current node is the root html element, then this is a parse error; ignore the token. (fragment case)

Otherwise, pop the current node (which will be a colgroup element) from the stack of open elements. Switch the insertion mode to "in table".

An end tag whose tag name is "col"

Parse error. Ignore the token.

An end-of-file token

If the current node is the root html element, then stop parsing. (fragment case)

Otherwise, act as described in the "anything else" entry below.

Anything else

Act as if an end tag with the tag name "colgroup" had been seen, and then, if that token wasn't ignored, reprocess the current token.

The fake end tag token here can only be ignored in the fragment case.

8.2.5.4.13 The "in table body" insertion mode

When the user agent is to apply the rules for the "in table body" insertion mode, the user agent must handle the token as follows:

A start tag whose tag name is "tr"

Clear the stack back to a table body context. (See below.)

Insert an HTML element for the token, then switch the insertion mode to "in row".

A start tag whose tag name is one of: "th", "td"

Parse error. Act as if a start tag with the tag name "tr" had been seen, then reprocess the current token.

An end tag whose tag name is one of: "tbody", "tfoot", "thead"

If the stack of open elements does not have an element in table scope with the same tag name as the token, this is a parse error. Ignore the token.

Otherwise:

Clear the stack back to a table body context. (See below.)

Pop the current node from the stack of open elements. Switch the insertion mode to "in table".

A start tag whose tag name is one of: "caption", "col", "colgroup", "tbody", "tfoot", "thead"
An end tag whose tag name is "table"

If the stack of open elements does not have a tbody, thead, or tfoot element in table scope, this is a parse error. Ignore the token. (fragment case)

Otherwise:

Clear the stack back to a table body context. (See below.)

Act as if an end tag with the same tag name as the current node ("tbody", "tfoot", or "thead") had been seen, then reprocess the current token.

An end tag whose tag name is one of: "body", "caption", "col", "colgroup", "html", "td", "th", "tr"

Parse error. Ignore the token.

Anything else

Process the token using the rules for the "in table" insertion mode.

When the steps above require the UA to clear the stack back to a table body context, it means that the UA must, while the current node is not a tbody, tfoot, thead, or html element, pop elements from the stack of open elements.

The current node being an html element after this process is a fragment case.

8.2.5.4.14 The "in row" insertion mode

When the user agent is to apply the rules for the "in row" insertion mode, the user agent must handle the token as follows:

A start tag whose tag name is one of: "th", "td"

Clear the stack back to a table row context. (See below.)

Insert an HTML element for the token, then switch the insertion mode to "in cell".

Insert a marker at the end of the list of active formatting elements.

An end tag whose tag name is "tr"

If the stack of open elements does not have an element in table scope with the same tag name as the token, this is a parse error. Ignore the token. (fragment case)

Otherwise:

Clear the stack back to a table row context. (See below.)

Pop the current node (which will be a tr element) from the stack of open elements. Switch the insertion mode to "in table body".

A start tag whose tag name is one of: "caption", "col", "colgroup", "tbody", "tfoot", "thead", "tr"
An end tag whose tag name is "table"

Act as if an end tag with the tag name "tr" had been seen, then, if that token wasn't ignored, reprocess the current token.

The fake end tag token here can only be ignored in the fragment case.

An end tag whose tag name is one of: "tbody", "tfoot", "thead"

If the stack of open elements does not have an element in table scope with the same tag name as the token, this is a parse error. Ignore the token.

Otherwise, act as if an end tag with the tag name "tr" had been seen, then reprocess the current token.

An end tag whose tag name is one of: "body", "caption", "col", "colgroup", "html", "td", "th"

Parse error. Ignore the token.

Anything else

Process the token using the rules for the "in table" insertion mode.

When the steps above require the UA to clear the stack back to a table row context, it means that the UA must, while the current node is not a tr element or an html element, pop elements from the stack of open elements.

The current node being an html element after this process is a fragment case.

8.2.5.4.15 The "in cell" insertion mode

When the user agent is to apply the rules for the "in cell" insertion mode, the user agent must handle the token as follows:

An end tag whose tag name is one of: "td", "th"

If the stack of open elements does not have an element in table scope with the same tag name as that of the token, then this is a parse error and the token must be ignored.

Otherwise:

Generate implied end tags.

Now, if the current node is not an element with the same tag name as the token, then this is a parse error.

Pop elements from the stack of open elements stack until an element with the same tag name as the token has been popped from the stack.

Clear the list of active formatting elements up to the last marker.

Switch the insertion mode to "in row".

A start tag whose tag name is one of: "caption", "col", "colgroup", "tbody", "td", "tfoot", "th", "thead", "tr"

If the stack of open elements does not have a td or th element in table scope, then this is a parse error; ignore the token. (fragment case)

Otherwise, close the cell (see below) and reprocess the current token.

An end tag whose tag name is one of: "body", "caption", "col", "colgroup", "html"

Parse error. Ignore the token.

An end tag whose tag name is one of: "table", "tbody", "tfoot", "thead", "tr"

If the stack of open elements does not have an element in table scope with the same tag name as that of the token (which can only happen for "tbody", "tfoot" and "thead", or in the fragment case), then this is a parse error and the token must be ignored.

Otherwise, close the cell (see below) and reprocess the current token.

Anything else

Process the token using the rules for the "in body" insertion mode.

Where the steps above say to close the cell, they mean to run the following algorithm:

  1. If the stack of open elements has a td element in table scope, then act as if an end tag token with the tag name "td" had been seen.

  2. Otherwise, the stack of open elements will have a th element in table scope; act as if an end tag token with the tag name "th" had been seen.

The stack of open elements cannot have both a td and a th element in table scope at the same time, nor can it have neither when the close the cell algorithm is invoked.

8.2.5.4.16 The "in select" insertion mode

When the user agent is to apply the rules for the "in select" insertion mode, the user agent must handle the token as follows:

A character token that is U+0000 NULL

Parse error. Ignore the token.

Any other character token

Insert the token's character into the current node.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

A start tag whose tag name is "option"

If the current node is an option element, act as if an end tag with the tag name "option" had been seen.

Insert an HTML element for the token.

A start tag whose tag name is "optgroup"

If the current node is an option element, act as if an end tag with the tag name "option" had been seen.

If the current node is an optgroup element, act as if an end tag with the tag name "optgroup" had been seen.

Insert an HTML element for the token.

An end tag whose tag name is "optgroup"

First, if the current node is an option element, and the node immediately before it in the stack of open elements is an optgroup element, then act as if an end tag with the tag name "option" had been seen.

If the current node is an optgroup element, then pop that node from the stack of open elements. Otherwise, this is a parse error; ignore the token.

An end tag whose tag name is "option"

If the current node is an option element, then pop that node from the stack of open elements. Otherwise, this is a parse error; ignore the token.

An end tag whose tag name is "select"

If the stack of open elements does not have an element in select scope with the same tag name as the token, this is a parse error. Ignore the token. (fragment case)

Otherwise:

Pop elements from the stack of open elements until a select element has been popped from the stack.

Reset the insertion mode appropriately.

A start tag whose tag name is "select"

Parse error. Act as if the token had been an end tag with the tag name "select" instead.

A start tag whose tag name is one of: "input", "keygen", "textarea"

Parse error.

If the stack of open elements does not have a select element in select scope, ignore the token. (fragment case)

Otherwise, act as if an end tag with the tag name "select" had been seen, and reprocess the token.

A start tag token whose tag name is "script"

Process the token using the rules for the "in head" insertion mode.

An end-of-file token

If the current node is not the root html element, then this is a parse error.

The current node can only be the root html element in the fragment case.

Stop parsing.

Anything else

Parse error. Ignore the token.

8.2.5.4.17 The "in select in table" insertion mode

When the user agent is to apply the rules for the "in select in table" insertion mode, the user agent must handle the token as follows:

A start tag whose tag name is one of: "caption", "table", "tbody", "tfoot", "thead", "tr", "td", "th"

Parse error. Act as if an end tag with the tag name "select" had been seen, and reprocess the token.

An end tag whose tag name is one of: "caption", "table", "tbody", "tfoot", "thead", "tr", "td", "th"

Parse error.

If the stack of open elements has an element in table scope with the same tag name as that of the token, then act as if an end tag with the tag name "select" had been seen, and reprocess the token. Otherwise, ignore the token.

Anything else

Process the token using the rules for the "in select" insertion mode.

8.2.5.4.18 The "after body" insertion mode

When the user agent is to apply the rules for the "after body" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Process the token using the rules for the "in body" insertion mode.

A comment token

Append a Comment node to the first element in the stack of open elements (the html element), with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

An end tag whose tag name is "html"

If the parser was originally created as part of the HTML fragment parsing algorithm, this is a parse error; ignore the token. (fragment case)

Otherwise, switch the insertion mode to "after after body".

An end-of-file token

Stop parsing.

Anything else

Parse error. Switch the insertion mode to "in body" and reprocess the token.

8.2.5.4.19 The "in frameset" insertion mode

When the user agent is to apply the rules for the "in frameset" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Insert the character into the current node.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

A start tag whose tag name is "frameset"

Insert an HTML element for the token.

An end tag whose tag name is "frameset"

If the current node is the root html element, then this is a parse error; ignore the token. (fragment case)

Otherwise, pop the current node from the stack of open elements.

If the parser was not originally created as part of the HTML fragment parsing algorithm (fragment case), and the current node is no longer a frameset element, then switch the insertion mode to "after frameset".

A start tag whose tag name is "frame"

Insert an HTML element for the token. Immediately pop the current node off the stack of open elements.

Acknowledge the token's self-closing flag, if it is set.

A start tag whose tag name is "noframes"

Process the token using the rules for the "in head" insertion mode.

An end-of-file token

If the current node is not the root html element, then this is a parse error.

The current node can only be the root html element in the fragment case.

Stop parsing.

Anything else

Parse error. Ignore the token.

8.2.5.4.20 The "after frameset" insertion mode

When the user agent is to apply the rules for the "after frameset" insertion mode, the user agent must handle the token as follows:

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Insert the character into the current node.

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

An end tag whose tag name is "html"

Switch the insertion mode to "after after frameset".

A start tag whose tag name is "noframes"

Process the token using the rules for the "in head" insertion mode.

An end-of-file token

Stop parsing.

Anything else

Parse error. Ignore the token.

8.2.5.4.21 The "after after body" insertion mode

When the user agent is to apply the rules for the "after after body" insertion mode, the user agent must handle the token as follows:

A comment token

Append a Comment node to the Document object with the data attribute set to the data given in the comment token.

A DOCTYPE token
A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE
A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

An end-of-file token

Stop parsing.

Anything else

Parse error. Switch the insertion mode to "in body" and reprocess the token.

8.2.5.4.22 The "after after frameset" insertion mode

When the user agent is to apply the rules for the "after after frameset" insertion mode, the user agent must handle the token as follows:

A comment token

Append a Comment node to the Document object with the data attribute set to the data given in the comment token.

A DOCTYPE token
A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE
A start tag whose tag name is "html"

Process the token using the rules for the "in body" insertion mode.

An end-of-file token

Stop parsing.

A start tag whose tag name is "noframes"

Process the token using the rules for the "in head" insertion mode.

Anything else

Parse error. Ignore the token.

8.2.5.5 The rules for parsing tokens in foreign content

When the user agent is to apply the rules for parsing tokens in foreign content, the user agent must handle the token as follows:

A character token that is U+0000 NULL

Parse error. Insert a U+FFFD REPLACEMENT CHARACTER character into the current node.

A character token that is one of U+0009 CHARACTER TABULATION, "LF" (U+000A), "FF" (U+000C), "CR" (U+000D), or U+0020 SPACE

Insert the token's character into the current node.

Any other character token

Insert the token's character into the current node.

Set the frameset-ok flag to "not ok".

A comment token

Append a Comment node to the current node with the data attribute set to the data given in the comment token.

A DOCTYPE token

Parse error. Ignore the token.

A start tag whose tag name is one of: "b", "big", "blockquote", "body", "br", "center", "code", "dd", "div", "dl", "dt", "em", "embed", "h1", "h2", "h3", "h4", "h5", "h6", "head", "hr", "i", "img", "li", "listing", "menu", "meta", "nobr", "ol", "p", "pre", "ruby", "s", "small", "span", "strong", "strike", "sub", "sup", "table", "tt", "u", "ul", "var"
A start tag whose tag name is "font", if the token has any attributes named "color", "face", or "size"

Parse error.

Pop an element from the stack of open elements, and then keep popping more elements from the stack of open elements until the current node is a MathML text integration point, an HTML integration point, or an element in the HTML namespace.

Then, reprocess the token.

Any other start tag

If the current node is an element in the MathML namespace, adjust MathML attributes for the token. (This fixes the case of MathML attributes that are not all lowercase.)

If the current node is an element in the SVG namespace, and the token's tag name is one of the ones in the first column of the following table, change the tag name to the name given in the corresponding cell in the second column. (This fixes the case of SVG elements that are not all lowercase.)

Tag name Element name
altglyph altGlyph
altglyphdef altGlyphDef
altglyphitem altGlyphItem
animatecolor animateColor
animatemotion animateMotion
animatetransform animateTransform
clippath clipPath
feblend feBlend
fecolormatrix feColorMatrix
fecomponenttransfer feComponentTransfer
fecomposite feComposite
feconvolvematrix feConvolveMatrix
fediffuselighting feDiffuseLighting
fedisplacementmap feDisplacementMap
fedistantlight feDistantLight
feflood feFlood
fefunca feFuncA
fefuncb feFuncB
fefuncg feFuncG
fefuncr feFuncR
fegaussianblur feGaussianBlur
feimage feImage
femerge feMerge
femergenode feMergeNode
femorphology feMorphology
feoffset feOffset
fepointlight fePointLight
fespecularlighting feSpecularLighting
fespotlight feSpotLight
fetile feTile
feturbulence feTurbulence
foreignobject foreignObject
glyphref glyphRef
lineargradient linearGradient
radialgradient radialGradient
textpath textPath

If the current node is an element in the SVG namespace, adjust SVG attributes for the token. (This fixes the case of SVG attributes that are not all lowercase.)

Adjust foreign attributes for the token. (This fixes the use of namespaced attributes, in particular XLink in SVG.)

Insert a foreign element for the token, in the same namespace as the current node.

If the token has its self-closing flag set, then run the appropriate steps from the following list:

If the token's tag name is "script"

Acknowledge the token's self-closing flag, and then act as if an end tag with the tag name "script" had been seen.

Otherwise

Pop the current node off the stack of open elements and acknowledge the token's self-closing flag.

An end tag whose tag name is "script", if the current node is a script element in the SVG namespace

Pop the current node off the stack of open elements.

Let the old insertion point have the same value as the current insertion point. Let the insertion point be just before the next input character.

Increment the parser's script nesting level by one. Set the parser pause flag to true.

Process the script element according to the SVG rules, if the user agent supports SVG. [SVG]

Even if this causes new characters to be inserted into the tokenizer, the parser will not be executed reentrantly, since the parser pause flag is true.

Decrement the parser's script nesting level by one. If the parser's script nesting level is zero, then set the parser pause flag to false.

Let the insertion point have the value of the old insertion point. (In other words, restore the insertion point to its previous value. This value might be the "undefined" value.)

Any other end tag

Run these steps:

  1. Initialize node to be the current node (the bottommost node of the stack).

  2. If node is not an element with the same tag name as the token, then this is a parse error.

  3. Loop: If node's tag name, converted to ASCII lowercase, is the same as the tag name of the token, pop elements from the stack of open elements until node has been popped from the stack, and then abort these steps.

  4. Set node to the previous entry in the stack of open elements.

  5. If node is not an element in the HTML namespace, return to the step labeled loop.

  6. Otherwise, process the token according to the rules given in the section corresponding to the current insertion mode in HTML content.