This specification provides a dustbin for the Web.

This specification is an experimental breakup of the HTML specification. You can see the full list on the index page and take part in the discussion in the repository.

Obsolete but conforming features

Features listed in this section will trigger warnings in conformance checkers.

Authors should not specify a border attribute on an img element. If the attribute is present, its value must be the string "0". CSS should be used instead.

Authors should not specify a language attribute on a script element. If the attribute is present, its value must be an ASCII case-insensitive match for the string "JavaScript" and either the type attribute must be omitted or its value must be an ASCII case-insensitive match for the string "text/javascript". The attribute should be entirely omitted instead (with the value "JavaScript", it has no effect), or replaced with use of the type attribute.

Authors should not specify the name attribute on a elements. If the attribute is present, its value must not be the empty string and must neither be equal to the value of any of the IDs in the element's home subtree other than the element's own ID, if any, nor be equal to the value of any of the other name attributes on a elements in the element's home subtree. If this attribute is present and the element has an ID, then the attribute's value must be equal to the element's ID. In earlier versions of the language, this attribute was intended as a way to specify possible targets for fragment identifiers in URLs. The id attribute should be used instead.

Authors should not, but may despite requirements to the contrary elsewhere in this specification, specify the maxlength and size attributes on input elements whose type attributes are in the Number state. One valid reason for using these attributes regardless is to help legacy user agents that do not support input elements with type="number" to still render the text field with a useful width.

In the HTML syntax, specifying a DOCTYPE that is an obsolete permitted DOCTYPE will also trigger a warning.

Warnings for obsolete but conforming features

To ease the transition from HTML4 Transitional documents to the language defined in this specification, and to discourage certain features that are only allowed in very few circumstances, conformance checkers must warn the user when the following features are used in a document. These are generally old obsolete features that have no effect, and are allowed only to distinguish between likely mistakes (regular conformance errors) and mere vestigial markup or unusual and discouraged practices (these warnings).

The following features must be categorised as described above:

Conformance checkers must distinguish between pages that have no conformance errors and have none of these obsolete features, and pages that have no conformance errors but do have some of these obsolete features.

For example, a validator could report some pages as "Valid HTML" and others as "Valid HTML with warnings".

Non-conforming features

Elements in the following list are entirely obsolete, and must not be used by authors:

applet

Use embed or object instead.

acronym

Use abbr instead.

bgsound

Use audio instead.

dir

Use ul instead.

frame
frameset
noframes

Either use iframe and CSS instead, or use server-side includes to generate complete pages with the various invariant parts merged in.

hgroup

To mark up subheadings, consider putting the subheading into a p element after the h1- h6 element containing the main heading, or putting the subheading directly within the h1- h6 element containing the main heading, but separated from the main heading by punctuation and/or within, for example, a span class="subheading" element with differentiated styling.

Headings and subheadings, alternative titles, or taglines can be grouped using the header or div elements.

isindex

Use an explicit form and text field combination instead.

listing

Use pre and code instead.

nextid

Use GUIDs instead.

noembed

Use object instead of embed when fallback is necessary.

plaintext

Use the "text/plain" MIME type instead.

strike

Use del instead if the element is marking an edit, otherwise use s instead.

xmp

Use pre and code instead, and escape "<" and "&" characters as "&lt;" and "&amp;" respectively.

basefont
big
blink
center
font
marquee
multicol
nobr
spacer
tt

Use appropriate elements or CSS instead.

Where the tt element would have been used for marking up keyboard input, consider the kbd element; for variables, consider the var element; for computer code, consider the code element; and for computer output, consider the samp element.

Similarly, if the big element is being used to denote a heading, consider using the h1 element; if it is being used for marking up important passages, consider the strong element; and if it is being used for highlighting text for reference purposes, consider the mark element.

See also the text-level semantics usage summary for more suggestions with examples.

The following attributes are obsolete (though the elements are still part of the language), and must not be used by authors:

charset on a elements
charset on link elements

Use an HTTP Content-Type header on the linked resource instead.

coords on a elements
shape on a elements

Use area instead of a for image maps.

methods on a elements
methods on link elements

Use the HTTP OPTIONS feature instead.

name on a elements (except as noted in the previous section)
name on embed elements
name on img elements
name on option elements

Use the id attribute instead.

rev on a elements
rev on link elements

Use the rel attribute instead, with an opposite term. (For example, instead of rev="made", use rel="author".)

urn on a elements
urn on link elements

Specify the preferred persistent identifier using the href attribute instead.

accept on form elements

Use the accept attribute directly on the input elements instead.

nohref on area elements

Omitting the href attribute is sufficient; the nohref attribute is unnecessary. Omit it altogether.

profile on head elements

When used for declaring which meta terms are used in the document, unnecessary; omit it altogether, and register the names.

When used for triggering specific user agent behaviours: use a link element instead.

version on html elements

Unnecessary. Omit it altogether.

ismap on input elements

Unnecessary. Omit it altogether. All input elements with a type attribute in the Image Button state are processed as server-side image maps.

usemap on input elements

Use img instead of input for image maps.

longdesc on iframe elements

Use a regular a element to link to the description.

lowsrc on img elements

Use a progressive JPEG image (given in the src attribute), instead of using two separate images.

target on link elements

Unnecessary. Omit it altogether.

scheme on meta elements

Use only one scheme per field, or make the scheme declaration part of the value.

archive on object elements
classid on object elements
code on object elements
codebase on object elements
codetype on object elements

Use the data and type attributes to invoke plugins. To set parameters with these names in particular, the param element can be used.

declare on object elements

Repeat the object element completely each time the resource is to be reused.

standby on object elements

Optimise the linked resource so that it loads quickly or, at least, incrementally.

type on param elements
valuetype on param elements

Use the name and value attributes without declaring value types.

language on script elements (except as noted in the previous section)

Use the type attribute instead.

event on script elements
for on script elements

Use DOM Events mechanisms to register event listeners. [[!DOM]]

media on source elements

Use script to select the media resource(s) to use.

datapagesize on table elements

Unnecessary. Omit it altogether.

summary on table elements

Use one of the techniques for describing tables given in the table section instead.

abbr on td elements

Use text that begins in an unambiguous and terse manner, and include any more elaborate text after that. The title attribute can also be useful in including more detailed text, so that the cell's contents can be made terse. If it's a heading, use th (which has an abbr attribute).

axis on td and th elements

Use the scope attribute on the relevant th.

scope on td elements

Use th elements for heading cells.

datasrc on a, applet, button, div, frame, iframe, img, input, label, legend, marquee, object, option, select, span, table, and textarea elements
datafld on a, applet, button, div, fieldset, frame, iframe, img, input, label, legend, marquee, object, param, select, span, and textarea elements
dataformatas on button, div, input, label, legend, marquee, object, option, select, span, and table elements

Use script and a mechanism such as XMLHttpRequest to populate the page dynamically. [[!XHR]]

alink on body elements
bgcolor on body elements
bottommargin on body elements
leftmargin on body elements
link on body elements
marginheight on body elements
marginwidth on body elements
rightmargin on body elements
text on body elements
margintop on body elements
vlink on body elements
clear on br elements
align on caption elements
align on col elements
char on col elements
charoff on col elements
valign on col elements
width on col elements
align on div elements
compact on dl elements
align on embed elements
hspace on embed elements
vspace on embed elements
align on hr elements
color on hr elements
noshade on hr elements
size on hr elements
width on hr elements
align on h1—h6 elements
align on iframe elements
allowtransparency on iframe elements
frameborder on iframe elements
hspace on iframe elements
marginheight on iframe elements
marginwidth on iframe elements
scrolling on iframe elements
vspace on iframe elements
align on input elements
border on input elements
hspace on input elements
vspace on input elements
align on img elements
border on img elements (except as noted in the previous section)
hspace on img elements
vspace on img elements
align on legend elements
type on li elements
compact on menu elements
align on object elements
border on object elements
hspace on object elements
vspace on object elements
compact on ol elements
align on p elements
width on pre elements
align on table elements
bgcolor on table elements
bordercolor on table elements
cellpadding on table elements
cellspacing on table elements
frame on table elements
height on table elements
hspace on table elements
rules on table elements
vspace on table elements
width on table elements
align on tbody, thead, and tfoot elements
char on tbody, thead, and tfoot elements
charoff on tbody, thead, and tfoot elements
valign on tbody, thead, and tfoot elements
align on td and th elements
bgcolor on td and th elements
char on td and th elements
charoff on td and th elements
height on td and th elements
nowrap on td and th elements
valign on td and th elements
width on td and th elements
align on tr elements
bgcolor on tr elements
char on tr elements
charoff on tr elements
height on tr elements
valign on tr elements
compact on ul elements
type on ul elements
background on body, table, thead, tbody, tfoot, tr, td, and th elements

Use CSS instead.

The border attribute on the table element can be used to provide basic fallback styling for the purpose of making tables legible in browsing environments where CSS support is limited or absent, such as text-based browsers, WYSIWYG editors, and in situations where CSS support is disabled or the style sheet is lost. Only the empty string and the value "1" may be used as border values for this purpose. Other values are considered obsolete. To regulate the thickness of such borders, authors should instead use CSS.

Requirements for implementations

The applet element

The applet element is a Java-specific variant of the embed element. The applet element is now obsoleted so that all extension frameworks (Java, .NET, Flash, etc) are handled in a consistent manner.

When the element matches any of the following conditions, it represents its contents:

Otherwise, the user agent should instantiate a Java Language runtime plugin, and should pass the names and values of all the attributes on the element, in the order they were added to the element, with the attributes added by the parser being ordered in source order, and then a parameter named "PARAM" whose value is null, and then all the names and values of parameters given by param elements that are children of the applet element, in tree order, to the plugin used. If the plugin supports a scriptable interface, the HTMLAppletElement object representing the element should expose that interface. The applet element represents the plugin.

The applet element is unaffected by the CSS 'display' property. The Java Language runtime is instantiated even if the element is hidden with a 'display:none' CSS style.

The applet element must implement the HTMLAppletElement interface.

interface HTMLAppletElement : HTMLElement {
  attribute DOMString align;
  attribute DOMString alt;
  attribute DOMString archive;
  attribute DOMString code;
  attribute DOMString codeBase;
  attribute DOMString height;
  attribute unsigned long hspace;
  attribute DOMString name;
  attribute DOMString _object; // the underscore is not part of the identifier 
  attribute unsigned long vspace;
  attribute DOMString width;
};

The align, alt, archive, code, height, hspace, name, object, vspace, and width IDL attributes must reflect the respective content attributes of the same name. For the purposes of reflection, the applet element's object content attribute is defined as containing a URL.

The codeBase IDL attribute must reflect the codebase content attribute, which for the purposes of reflection is defined as containing a URL.

The marquee element

The marquee element is a presentational element that animates content. CSS transitions and animations are a more appropriate mechanism. [[!CSSANIMATIONS]] [[CSSTRANSITIONS]]

The task source for tasks mentioned in this section is the DOM manipulation task source.

The marquee element must implement the HTMLMarqueeElement interface.

interface HTMLMarqueeElement : HTMLElement {
  attribute DOMString behavior;
  attribute DOMString bgColor;
  attribute DOMString direction;
  attribute DOMString height;
  attribute unsigned long hspace;
  attribute long loop;
  attribute unsigned long scrollAmount;
  attribute unsigned long scrollDelay;
  attribute boolean trueSpeed;
  attribute unsigned long vspace;
  attribute DOMString width;

  attribute EventHandler onbounce;
  attribute EventHandler onfinish;
  attribute EventHandler onstart;

  void start();
  void stop();
};

A marquee element can be turned on or turned off. When it is created, it is turned on.

When the start() method is called, the marquee element must be turned on.

When the stop() method is called, the marquee element must be turned off.

When a marquee element is created, the user agent must queue a task to fire a simple event named start at the element.

The behavior content attribute on marquee elements is an enumerated attribute with the following keywords (all non-conforming):

Keyword State
scroll scroll
slide slide
alternate alternate

The missing value default is the scroll state.

The direction content attribute on marquee elements is an enumerated attribute with the following keywords (all non-conforming):

Keyword State
left left
right right
up up
down down

The missing value default is the left state.

The truespeed content attribute on marquee elements is a boolean attribute.

A marquee element has a marquee scroll interval, which is obtained as follows:

  1. If the element has a scrolldelay attribute, and parsing its value using the rules for parsing non-negative integers does not return an error, then let delay be the parsed value. Otherwise, let delay be 85.

  2. If the element does not have a truespeed attribute, and the delay value is less than 60, then let delay be 60 instead.

  3. The marquee scroll interval is delay, interpreted in milliseconds.

A marquee element has a marquee scroll distance, which, if the element has a scrollamount attribute, and parsing its value using the rules for parsing non-negative integers does not return an error, is the parsed value interpreted in CSS pixels, and otherwise is 6 CSS pixels.

A marquee element has a marquee loop count, which, if the element has a loop attribute, and parsing its value using the rules for parsing integers does not return an error or a number less than 1, is the parsed value, and otherwise is −1.

The loop IDL attribute, on getting, must return the element's marquee loop count; and on setting, if the new value is different than the element's marquee loop count and either greater than zero or equal to −1, must set the element's loop content attribute (adding it if necessary) to the valid integer that represents the new value. (Other values are ignored.)

A marquee element also has a marquee current loop index, which is zero when the element is created.

The rendering layer will occasionally increment the marquee current loop index, which must cause the following steps to be run:

  1. If the marquee loop count is −1, then abort these steps.

  2. Increment the marquee current loop index by one.

  3. If the marquee current loop index is now equal to or greater than the element's marquee loop count, turn off the marquee element and queue a task to fire a simple event named finish at the marquee element.

    Otherwise, if the behavior attribute is in the alternate state, then queue a task to fire a simple event named bounce at the marquee element.

    Otherwise, queue a task to fire a simple event named start at the marquee element.

The following are the event handlers (and their corresponding event handler event types) that must be supported, as event handler content attributes and event handler IDL attributes, by marquee elements:

Event handler Event handler event type
onbounce bounce
onfinish finish
onstart start

The behavior, direction, height, hspace, vspace, and width IDL attributes must reflect the respective content attributes of the same name.

The bgColor IDL attribute must reflect the bgcolor content attribute.

The scrollAmount IDL attribute must reflect the scrollamount content attribute. The default value is 6.

The scrollDelay IDL attribute must reflect the scrolldelay content attribute. The default value is 85.

The trueSpeed IDL attribute must reflect the truespeed content attribute.

Frames

The frameset element acts as the body element in documents that use frames.

The frameset element must implement the HTMLFrameSetElement interface.

interface HTMLFrameSetElement : HTMLElement {
  attribute DOMString cols;
  attribute DOMString rows;
};
HTMLFrameSetElement implements WindowEventHandlers;

The cols and rows IDL attributes of the frameset element must reflect the respective content attributes of the same name.

The frameset element exposes as event handler content attributes a number of the event handlers of the Window object. It also mirrors their event handler IDL attributes.

The onblur, onerror, onfocus, onload, onresize, and onscroll event handlers of the Window object, exposed on the frameset element, replace the generic event handlers with the same names normally supported by HTML elements.

The frame element defines a nested browsing context similar to the iframe element, but rendered within a frameset element.

A frame element is said to be an active frame element when it is in a Document.

When a frame element is created as an active frame element, or becomes an active frame element after not having been one, the user agent must create a nested browsing context, and then process the frame attributes for the first time.

When a frame element stops being an active frame element, the user agent must discard the nested browsing context.

Whenever a frame element with a nested browsing context has its src attribute set, changed, or removed, the user agent must process the frame attributes.

When the user agent is to process the frame attributes, it must run the first appropriate steps from the following list:

If the element has no src attribute specified, and the user agent is processing the frame's attributes for the first time

Queue a task to fire a simple event named load at the frame element.

Otherwise

  1. If the value of the src attribute is the empty string, let url be the string "about:blank".

    Otherwise, resolve the value of the src attribute, relative to the frame element.

    If that is not successful, then let url be the string "about:blank". Otherwise, let url be the resulting absolute URL.

  2. Navigate the element's child browsing context to url.

Any navigation required of the user agent in the process the frame attributes algorithm must be completed as an explicit self-navigation override and with the frame element's node document's browsing context as the source browsing context.

Furthermore, if the active document of the element's child browsing context before such a navigation was not completely loaded at the time of the new navigation, then the navigation must be completed with replacement enabled.

Similarly, if the child browsing context's session history contained only one Document when the process the frame attributes algorithm was invoked, and that was the about:blank Document created when the child browsing context was created, then any navigation required of the user agent in that algorithm must be completed with replacement enabled.

When a Document in a frame is marked as completely loaded, the user agent must queue a task to fire a simple event named load at the frame element.

The task source for the tasks above is the DOM manipulation task source.

When a frame element's nested browsing context's active document is not ready for post-load tasks, and when anything is delaying the load event of the frame element's browsing context's active document, and when the frame element's browsing context is in the delaying load events mode, the frame must delay the load event of its document.

When the browsing context is created, if a name attribute is present, the browsing context name must be set to the value of this attribute; otherwise, the browsing context name must be set to the empty string.

Whenever the name attribute is set, the nested browsing context's name must be changed to the new value. If the attribute is removed, the browsing context name must be set to the empty string.

The frame element must implement the HTMLFrameElement interface.

interface HTMLFrameElement : HTMLElement {
  attribute DOMString name;
  attribute DOMString scrolling;
  attribute DOMString src;
  attribute DOMString frameBorder;
  attribute DOMString longDesc;
  attribute boolean noResize;
  readonly attribute Document? contentDocument;
  readonly attribute WindowProxy? contentWindow;

  [TreatNullAs=EmptyString] attribute DOMString marginHeight;
  [TreatNullAs=EmptyString] attribute DOMString marginWidth;
};

The name, scrolling, and src IDL attributes of the frame element must reflect the respective content attributes of the same name. For the purposes of reflection, the frame element's src content attribute is defined as containing a URL.

The frameBorder IDL attribute of the frame element must reflect the element's frameborder content attribute.

The longDesc IDL attribute of the frame element must reflect the element's longdesc content attribute, which for the purposes of reflection is defined as containing a URL.

The noResize IDL attribute of the frame element must reflect the element's noresize content attribute.

The contentDocument IDL attribute of the frame element must return the Document object of the active document of the frame element's nested browsing context, if any and if its effective script origin is the same origin as the effective script origin specified by the incumbent settings object, or null otherwise.

The contentWindow IDL attribute must return the WindowProxy object of the frame element's nested browsing context.

The marginHeight IDL attribute of the frame element must reflect the element's marginheight content attribute.

The marginWidth IDL attribute of the frame element must reflect the element's marginwidth content attribute.

Other elements, attributes and APIs

User agents must treat acronym elements in a manner equivalent to abbr elements in terms of semantics and for purposes of rendering.

partial interface HTMLAnchorElement {
  attribute DOMString coords;
  attribute DOMString charset;
  attribute DOMString name;
  attribute DOMString rev;
  attribute DOMString shape;
};

The coords, charset, name, rev, and shape IDL attributes of the a element must reflect the respective content attributes of the same name.

partial interface HTMLAreaElement {
  attribute boolean noHref;
};

The noHref IDL attribute of the area element must reflect the element's nohref content attribute.

partial interface HTMLBodyElement {
  [TreatNullAs=EmptyString] attribute DOMString text;
  [TreatNullAs=EmptyString] attribute DOMString link;
  [TreatNullAs=EmptyString] attribute DOMString vLink;
  [TreatNullAs=EmptyString] attribute DOMString aLink;
  [TreatNullAs=EmptyString] attribute DOMString bgColor;
                   attribute DOMString background;
};

The text IDL attribute of the body element must reflect the element's text content attribute.

The link IDL attribute of the body element must reflect the element's link content attribute.

The aLink IDL attribute of the body element must reflect the element's alink content attribute.

The vLink IDL attribute of the body element must reflect the element's vlink content attribute.

The bgColor IDL attribute of the body element must reflect the element's bgcolor content attribute.

The background IDL attribute of the body element must reflect the element's background content attribute. (The background content is not defined to contain a URL, despite rules regarding its handling in the rendering section above.)

partial interface HTMLBRElement {
  attribute DOMString clear;
};

The clear IDL attribute of the br element must reflect the content attribute of the same name.

partial interface HTMLTableCaptionElement {
  attribute DOMString align;
};

The align IDL attribute of the caption element must reflect the content attribute of the same name.

partial interface HTMLTableColElement {
  attribute DOMString align;
  attribute DOMString ch;
  attribute DOMString chOff;
  attribute DOMString vAlign;
  attribute DOMString width;
};

The align and width IDL attributes of the col element must reflect the respective content attributes of the same name.

The ch IDL attribute of the col element must reflect the element's char content attribute.

The chOff IDL attribute of the col element must reflect the element's charoff content attribute.

The vAlign IDL attribute of the col element must reflect the element's valign content attribute.

User agents must treat dir elements in a manner equivalent to ul elements in terms of semantics and for purposes of rendering.

The dir element must implement the HTMLDirectoryElement interface.

interface HTMLDirectoryElement : HTMLElement {
  attribute boolean compact;
};

The compact IDL attribute of the dir element must reflect the content attribute of the same name.

partial interface HTMLDivElement {
  attribute DOMString align;
};

The align IDL attribute of the div element must reflect the content attribute of the same name.

partial interface HTMLDListElement {
  attribute boolean compact;
};

The compact IDL attribute of the dl element must reflect the content attribute of the same name.

partial interface HTMLEmbedElement {
  attribute DOMString align;
  attribute DOMString name;
};

The name and align IDL attributes of the embed element must reflect the respective content attributes of the same name.

The font element must implement the HTMLFontElement interface.

interface HTMLFontElement : HTMLElement {
  [TreatNullAs=EmptyString] attribute DOMString color;
                   attribute DOMString face;
                   attribute DOMString size; 
};

The color, face, and size IDL attributes of the font element must reflect the respective content attributes of the same name.

partial interface HTMLHeadingElement {
  attribute DOMString align;
};

The align IDL attribute of the h1–h6 elements must reflect the content attribute of the same name.

The profile IDL attribute on head elements (with the HTMLHeadElement interface) is intentionally omitted. Unless so required by another applicable specification, implementations would therefore not support this attribute. (It is mentioned here as it was defined in a previous version of the DOM specifications.)

partial interface HTMLHRElement {
  attribute DOMString align;
  attribute DOMString color;
  attribute boolean noShade;
  attribute DOMString size;
  attribute DOMString width;
};

The align, color, size, and width IDL attributes of the hr element must reflect the respective content attributes of the same name.

The noShade IDL attribute of the hr element must reflect the element's noshade content attribute.

partial interface HTMLHtmlElement {
  attribute DOMString version;
};

The version IDL attribute of the html element must reflect the content attribute of the same name.

partial interface HTMLIFrameElement {
  attribute DOMString align;
  attribute DOMString scrolling;
  attribute DOMString frameBorder;
  attribute DOMString longDesc;

  [TreatNullAs=EmptyString] attribute DOMString marginHeight;
  [TreatNullAs=EmptyString] attribute DOMString marginWidth;
};

The align and scrolling IDL attributes of the iframe element must reflect the respective content attributes of the same name.

The frameBorder IDL attribute of the iframe element must reflect the element's frameborder content attribute.

The longDesc IDL attribute of the iframe element must reflect the element's longdesc content attribute, which for the purposes of reflection is defined as containing a URL.

The marginHeight IDL attribute of the iframe element must reflect the element's marginheight content attribute.

The marginWidth IDL attribute of the iframe element must reflect the element's marginwidth content attribute.

partial interface HTMLImageElement {
  attribute DOMString name;
  attribute DOMString lowsrc;
  attribute DOMString align;
  attribute unsigned long hspace;
  attribute unsigned long vspace;
  attribute DOMString longDesc;

  [TreatNullAs=EmptyString] attribute DOMString border;
};

The name, align, border, hspace, and vspace IDL attributes of the img element must reflect the respective content attributes of the same name.

The longDesc IDL attribute of the img element must reflect the element's longdesc content attribute, which for the purposes of reflection is defined as containing a URL.

The lowsrc IDL attribute of the img element must reflect the element's lowsrc content attribute, which for the purposes of reflection is defined as containing a URL.

partial interface HTMLInputElement {
  attribute DOMString align;
  attribute DOMString useMap;
};

The align IDL attribute of the input element must reflect the content attribute of the same name.

The useMap IDL attribute of the input element must reflect the element's usemap content attribute.

partial interface HTMLLegendElement {
  attribute DOMString align;
};

The align IDL attribute of the legend element must reflect the content attribute of the same name.

partial interface HTMLLIElement {
  attribute DOMString type;
};

The type IDL attribute of the li element must reflect the content attribute of the same name.

partial interface HTMLLinkElement {
  attribute DOMString charset;
  attribute DOMString rev;
  attribute DOMString target;
};

The charset, rev, and target IDL attributes of the link element must reflect the respective content attributes of the same name.

User agents must treat listing elements in a manner equivalent to pre elements in terms of semantics and for purposes of rendering.

partial interface HTMLMenuElement {
  attribute boolean compact;
};

The compact IDL attribute of the menu element must reflect the content attribute of the same name.

partial interface HTMLMetaElement {
  attribute DOMString scheme;
};

User agents may treat the scheme content attribute on the meta element as an extension of the element's name content attribute when processing a meta element with a name attribute whose value is one that the user agent recognizes as supporting the scheme attribute.

User agents are encouraged to ignore the scheme attribute and instead process the value given to the metadata name as if it had been specified for each expected value of the scheme attribute.

For example, if the user agent acts on meta elements with name attributes having the value "eGMS.subject.keyword", and knows that the scheme attribute is used with this metadata name, then it could take the scheme attribute into account, acting as if it was an extension of the name attribute. Thus the following two meta elements could be treated as two elements giving values for two different metadata names, one consisting of a combination of "eGMS.subject.keyword" and "LGCL", and the other consisting of a combination of "eGMS.subject.keyword" and "ORLY":

<!-- this markup is invalid -->
<meta name="eGMS.subject.keyword" scheme="LGCL" content="Abandoned vehicles">
<meta name="eGMS.subject.keyword" scheme="ORLY" content="Mah car: kthxbye">

The suggested processing of this markup, however, would be equivalent to the following:

<meta name="eGMS.subject.keyword" content="Abandoned vehicles">
<meta name="eGMS.subject.keyword" content="Mah car: kthxbye">

The scheme IDL attribute of the meta element must reflect the content attribute of the same name.

partial interface HTMLObjectElement {
  attribute DOMString align;
  attribute DOMString archive;
  attribute DOMString code;
  attribute boolean declare;
  attribute unsigned long hspace;
  attribute DOMString standby;
  attribute unsigned long vspace;
  attribute DOMString codeBase;
  attribute DOMString codeType;

  [TreatNullAs=EmptyString] attribute DOMString border;
};

The align, archive, border, code, declare, hspace, standby, and vspace IDL attributes of the object element must reflect the respective content attributes of the same name.

The codeBase IDL attribute of the object element must reflect the element's codebase content attribute, which for the purposes of reflection is defined as containing a URL.

The codeType IDL attribute of the object element must reflect the element's codetype content attribute.

partial interface HTMLOListElement {
  attribute boolean compact;
};

The compact IDL attribute of the ol element must reflect the content attribute of the same name.

partial interface HTMLParagraphElement {
  attribute DOMString align;
};

The align IDL attribute of the p element must reflect the content attribute of the same name.

partial interface HTMLParamElement {
  attribute DOMString type;
  attribute DOMString valueType;
};

The type IDL attribute of the param element must reflect the content attribute of the same name.

The valueType IDL attribute of the param element must reflect the element's valuetype content attribute.

User agents must treat plaintext elements in a manner equivalent to pre elements in terms of semantics and for purposes of rendering. (The parser has special behaviour for this element, though.)

partial interface HTMLPreElement {
  attribute long width;
};

The width IDL attribute of the pre element must reflect the content attribute of the same name.

partial interface HTMLScriptElement {
  attribute DOMString event;
  attribute DOMString htmlFor;
};

The event and htmlFor IDL attributes of the script element must return the empty string on getting, and do nothing on setting.

partial interface HTMLTableElement {attribute DOMString frame;
  attribute DOMString rules;
  attribute DOMString summary;
  attribute DOMString width;

  [TreatNullAs=EmptyString] attribute DOMString bgColor;
  [TreatNullAs=EmptyString] attribute DOMString cellPadding;
  [TreatNullAs=EmptyString] attribute DOMString cellSpacing;
};

The align, border, frame, summary, rules, and width, IDL attributes of the table element must reflect the respective content attributes of the same name.

The bgColor IDL attribute of the table element must reflect the element's bgcolor content attribute.

The cellPadding IDL attribute of the table element must reflect the element's cellpadding content attribute.

The cellSpacing IDL attribute of the table element must reflect the element's cellspacing content attribute.

partial interface HTMLTableSectionElement {
  attribute DOMString align;
  attribute DOMString ch;
  attribute DOMString chOff;
  attribute DOMString vAlign;
};

The align IDL attribute of the tbody, thead, and tfoot elements must reflect the content attribute of the same name.

The ch IDL attribute of the tbody, thead, and tfoot elements must reflect the elements' char content attributes.

The chOff IDL attribute of the tbody, thead, and tfoot elements must reflect the elements' charoff content attributes.

The vAlign IDL attribute of the tbody, thead, and tfoot element must reflect the elements' valign content attributes.

partial interface HTMLTableCellElement {
  attribute DOMString align;
  attribute DOMString axis;
  attribute DOMString height;
  attribute DOMString width;

  attribute DOMString ch;
  attribute DOMString chOff;
  attribute boolean noWrap;
  attribute DOMString vAlign;

  [TreatNullAs=EmptyString] attribute DOMString bgColor;
};

The align, axis, height, and width IDL attributes of the td and th elements must reflect the respective content attributes of the same name.

The ch IDL attribute of the td and th elements must reflect the elements' char content attributes.

The chOff IDL attribute of the td and th elements must reflect the elements' charoff content attributes.

The noWrap IDL attribute of the td and th elements must reflect the elements' nowrap content attributes.

The vAlign IDL attribute of the td and th element must reflect the elements' valign content attributes.

The bgColor IDL attribute of the td and th elements must reflect the elements' bgcolor content attributes.

partial interface HTMLTableDataCellElement {
  attribute DOMString abbr;
};

The abbr IDL attribute of the td element must reflect the respective content attributes of the same name.

partial interface HTMLTableRowElement {
  attribute DOMString align;
  attribute DOMString ch;
  attribute DOMString chOff;
  attribute DOMString vAlign;

  [TreatNullAs=EmptyString] attribute DOMString bgColor;
};

The align IDL attribute of the tr element must reflect the content attribute of the same name.

The ch IDL attribute of the tr element must reflect the element's char content attribute.

The chOff IDL attribute of the tr element must reflect the element's charoff content attribute.

The vAlign IDL attribute of the tr element must reflect the element's valign content attribute.

The bgColor IDL attribute of the tr element must reflect the element's bgcolor content attribute.

partial interface HTMLUListElement {
  attribute boolean compact;
  attribute DOMString type;
};

The compact and type IDL attributes of the ul element must reflect the respective content attributes of the same name.

User agents must treat xmp elements in a manner equivalent to pre elements in terms of semantics and for purposes of rendering. (The parser has special behaviour for this element though.)

The blink, bgsound, isindex, multicol, nextid, and spacer elements must use the HTMLUnknownElement interface.

partial interface Document {
  [TreatNullAs=EmptyString] attribute DOMString fgColor;
  [TreatNullAs=EmptyString] attribute DOMString linkColor;
  [TreatNullAs=EmptyString] attribute DOMString vlinkColor;
  [TreatNullAs=EmptyString] attribute DOMString alinkColor;
  [TreatNullAs=EmptyString] attribute DOMString bgColor;

  readonly attribute HTMLCollection anchors;
  readonly attribute HTMLCollection applets;

  void clear();
  void captureEvents();
  void releaseEvents();

  readonly attribute HTMLAllCollection all;
};

The attributes of the Document object listed in the first column of the following table must reflect the content attribute on the body element with the name given in the corresponding cell in the second column on the same row, if the body element is a body element (as opposed to a frameset element). When there is no body element or if it is a frameset element, the attributes must instead return the empty string on getting and do nothing on setting.

IDL attribute Content attribute
fgColor text
linkColor link
vlinkColor vlink
alinkColor alink
bgColor bgcolor

The anchors attribute must return an HTMLCollection rooted at the Document node, whose filter matches only a elements with name attributes.

The applets attribute must return an HTMLCollection rooted at the Document node, whose filter matches only applet elements.

The clear(), captureEvents(), and releaseEvents() methods must do nothing.

The all attribute must return an HTMLAllCollection rooted at the Document node, whose filter matches all elements.

The object returned for all has several unusual behaviours:

These requirements are a willful violation of the JavaScript specification current at the time of writing (ECMAScript edition 5). The JavaScript specification requires that the ToBoolean() operator convert all objects to the true value, and does not have provisions for objects acting as if they were undefined for the purposes of certain operators. This violation is motivated by a desire for compatibility with two classes of legacy content: one that uses the presence of document.all as a way to detect legacy user agents, and one that only supports those legacy user agents and uses the document.all object without testing for its presence first. [[!ECMA262]]

partial interface Window {
  void captureEvents();
  void releaseEvents();
};

The captureEvents() and releaseEvents() methods must do nothing.

The hgroup element does not have strong native semantics or default implicit ARIA semantics. User agents must not implement accessibility layer semantics for the hgroup element that obfuscates or modifies the semantics of its children.