Status: Last call for comments
Features listed in this section will trigger warnings in conformance checkers.
Authors should not specify an http-equiv attribute in the
  Content
  Language state on a meta element. The lang attribute should be used instead.
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.
In the HTML syntax, specifying a DOCTYPE that is an obsolete permitted DOCTYPE will also trigger a warning.
The summary
  attribute, defined in the table section, will also
  trigger a warning.
Status: Last call for comments
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 are required to 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 categorized as described above:
The presence of an obsolete permitted DOCTYPE in an HTML document.
The presence of a meta element with an http-equiv attribute in the
   Content
   Language state.
The presence of a border attribute on an
   img element if its value is the string "0".
The presence of a language attribute on a
   script element if its value is an ASCII
   case-insensitive match for the string "JavaScript" and if there is no type attribute or there is and its
   value is an ASCII case-insensitive match for the
   string "text/javascript".
The presence of a name
   attribute on an a element, if its value is not the
   empty string.
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".
Status: Last call for comments
Elements in the following list are entirely obsolete, and must not be used by authors:
appletacronymUse abbr instead.
bgsoundUse audio instead.
dirUse ul instead.
frameframesetnoframesEither use iframe and CSS instead, or use server-side includes to generate complete pages with the various invariant parts merged in.
isindexUse an explicit form and text field combination instead.
listingxmpnextidUse GUIDs instead.
noembedplaintextUse the "text/plain" MIME type instead.
rbProviding the ruby base directly inside the ruby element is sufficient; the rb element is unnecessary. Omit it altogether.
basefontbigblinkcenterfontmarqueemulticolnobrsspacerstrikettuwbrUse appropriate elements and/or CSS instead.
For the s and strike elements, if
    they are marking up a removal from the element, consider using the
    del element 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 u element is being used to
    indicate emphasis, consider using the em element; if
    it is being used for marking up keywords, consider the
    b 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 elementscharset on link elementsUse an HTTP Content-Type header on the linked resource instead.
coords on a elementsshape on a elementsmethods on a elementsUse the HTTP OPTIONS feature instead.
name on a elements (except as noted in the previous section)name on embed elementsname on img elementsUse the id attribute instead.
rev on a elementsrev on link elementsUse the rel
   attribute instead, with an opposite term. (For example, instead of
   rev="made", use rel="author".)
urn on a elementsSpecify the preferred persistent identifier using the href attribute instead.
nohref on area elementsOmitting the href
   attribute is sufficient; the nohref attribute is
   unnecessary. Omit it altogether.
profile on head elementsWhen 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 behaviors: use
   a link element instead.
version on html elementsUnnecessary. Omit it altogether.
usemap on input elementslongdesc on iframe elementslongdesc on img elementsUse a regular a element to link to the description.
target on link elementsUnnecessary. Omit it altogether.
scheme on meta elementsUse only one scheme per field, or make the scheme declaration part of the value.
archive on object elementsclassid on object elementscode on object elementscodebase on object elementscodetype on object elementsUse 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 elementsRepeat the object element completely each time the resource is to be reused.
standby on object elementsOptimise the linked resource so that it loads quickly or, at least, incrementally.
type on param elementsvaluetype on param elementsUse 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 elementsfor on script elementsUse DOM Events mechanisms to register event listeners. [DOMEVENTS]
datapagesize on table elementsUnnecessary. Omit it altogether.
abbr on td and th elementsUse text that begins in an unambiguous and terse manner, and include any more elaborate text after that.
axis on td and th elementsUse the scope attribute.
datasrc on any elementdatafld on any elementdataformatas on any elementUse script and a mechanism such as XMLHttpRequest to populate the page dynamically. [XHR]
alink on body elementsbackground on body elementsbgcolor on body elementslink on body elementstext on body elementsvlink on body elementsclear on br elementsalign on caption elementsalign on col elementschar on col elementscharoff on col elementsvalign on col elementswidth on col elementsalign on div elementscompact on dl elementsalign on embed elementsalign on hr elementscolor on hr elementsnoshade on hr elementssize on hr elementswidth on hr elementsalign on h1—h6 elementsalign on iframe elementsframeborder on iframe elementsmarginheight on iframe elementsmarginwidth on iframe elementsscrolling on iframe elementsalign on input elementsalign on img elementsborder on img elements (except as noted in the previous section)hspace on img elementsvspace on img elementsalign on legend elementstype on li elementscompact on menu elementsalign on object elementsborder on object elementshspace on object elementsvspace on object elementscompact on ol elementstype on ol elementsalign on p elementswidth on pre elementsalign on table elementsbgcolor on table elementsborder on table elementscellpadding on table elementscellspacing on table elementsframe on table elementsrules on table elementswidth on table elementsalign on tbody, thead, and tfoot elementschar on tbody, thead, and tfoot elementscharoff on tbody, thead, and tfoot elementsvalign on tbody, thead, and tfoot elementsalign on td and th elementsbgcolor on td and th elementschar on td and th elementscharoff on td and th elementsheight on td and th elementsnowrap on td and th elementsvalign on td and th elementswidth on td and th elementsalign on tr elementsbgcolor on tr elementschar on tr elementscharoff on tr elementsvalign on tr elementscompact on ul elementstype on ul elementsUse CSS instead.
Status: Last call for comments
applet elementStatus: Last call for comments
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 is still in the
  stack of open elements of an HTML parser
  or XML parser, and when the element is not in a
  Document, and when the element's document is not
  fully active, and when the element's
  Document's browsing context had its
  sandboxed plugins browsing context flag when that
  Document was created, and when the element's
  Document was parsed from a resource whose sniffed type as determined
  during navigation is
  text/html-sandboxed, and when the element has an
  ancestor media element, and when the element has an
  ancestor object element that is not showing
  its fallback content, and when no Java Language runtime
  plugin is available, and when one is available
  but it is disabled, the element 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.
The codeBase
  IDL attribute must reflect the codebase content attribute.
marquee elementStatus: Last call for comments
The marquee element is a presentational element that
  animates content. CSS transitions and animations are a more
  appropriate mechanism.
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 DOMString trueSpeed; attribute unsigned long vspace; attribute DOMString width; attribute Function onbounce; attribute Function onfinish; attribute Function 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 an enumerated
  attribute with the following keywords (all
  non-conforming):
| Keyword | State | 
|---|---|
| true | true | 
| false | false | 
The missing value default is the false state.
A marquee element has a marquee scroll
  interval, which is obtained as follows:
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.
If the element does not have a truespeed attribute, or if it
   does but that attribute is in the false state, and the
   delay value is less than 60, then let delay be 60 instead.
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:
If the marquee loop count is −1, then abort these steps.
Increment the marquee current loop index by one.
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 content and 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.
Status: Last call for comments
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; attribute Function onafterprint; attribute Function onbeforeprint; attribute Function onbeforeunload; attribute Function onblur; attribute Function onerror; attribute Function onfocus; attribute Function onhashchange; attribute Function onload; attribute Function onmessage; attribute Function onoffline; attribute Function ononline; attribute Function onpagehide; attribute Function onpageshow; attribute Function onpopstate; attribute Function onredo; attribute Function onresize; attribute Function onstorage; attribute Function onundo; attribute Function onunload; };
The cols and
  rows IDL
  attributes of the frameset element must
  reflect the respective content attributes of the same
  name.
The frameset element must support the following
  event handler content attributes exposing the
  event handlers of the Window object:
onafterprintonbeforeprintonbeforeunloadonbluronerroronfocusonhashchangeonloadonmessageonofflineononlineonpagehideonpageshowonpopstateonredoonresizeonstorageonundoonunloadThe DOM interface also exposes event handler IDL
  attributes that mirror those on the Window
  element.
The onblur, onerror, onfocus, and onload event handler IDL
  attributes of the Window object, exposed on the
  frameset element, shadow the generic event
  handler IDL attributes 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.
When the browsing context is created, if a src attribute is present, the user
  agent must resolve the value of
  that attribute, relative to the element, and if that is successful,
  must then navigate the element's browsing context to
  the resulting absolute URL, with replacement
  enabled, and with the frame element's
  document's browsing context as the source
  browsing context.
Whenever the src attribute
  is set, the user agent must resolve the value of that attribute, relative to the
  element, and if that is successful, the nested browsing
  context must be navigated to
  the resulting absolute URL, with the
  frame element's document's browsing
  context as the source browsing context.
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.
When content loads in a frame, after any load events are fired within the content
  itself, the user agent must queue a task to fire
  a simple event named load at
  the frame element. When content fails to load (e.g. due
  to a network error), then the user agent must queue a
  task to fire a simple event named error at the element instead.
The task source for the tasks above is the DOM manipulation task source.
When there is an active parser in the
  frame, and when anything in the frame is
  delaying the load event of
  the frame's browsing context's
  active document, the frame must
  delay the load event of its document.
The frame element must implement the
  HTMLFrameElement interface.
interface HTMLFrameElement : HTMLElement { attribute DOMString frameBorder; attribute DOMString longDesc; attribute DOMString marginHeight; attribute DOMString marginWidth; attribute DOMString name; attribute boolean noResize; attribute DOMString scrolling; attribute DOMString src; readonly attribute Document contentDocument; };
The name, scrolling, and src IDL attributes of the
  frame element must reflect the respective
  content attributes of the same name.
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.
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.
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.
ISSUE-82 (profile-disambiguation) and ISSUE-99 (meta-scheme) block progress to Last Call
User agents must treat acronym elements in a manner
  equivalent to abbr elements.
[Supplemental] 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.
[Supplemental] interface HTMLAreaElement { attribute boolean noHref; };
The noHref IDL
  attribute of the area element must reflect
  the element's nohref content
  attribute.
The basefont element must implement the
  HTMLBaseFontElement interface.
interface HTMLBaseFontElement : HTMLElement { attribute DOMString color; attribute DOMString face; attribute long size; };
The color,
  face, and size IDL attributes of
  the basefont element must reflect the
  respective content attributes of the same name.
[Supplemental] interface HTMLBodyElement { attribute DOMString text; attribute DOMString bgColor; attribute DOMString background; attribute DOMString link; attribute DOMString vLink; attribute DOMString aLink; };
The text IDL
  attribute of the body element must reflect
  the element's text 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.)
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.
[Supplemental] interface HTMLBRElement { attribute DOMString clear; };
The clear IDL
  attribute of the br element must reflect
  the content attribute of the same name.
[Supplemental] interface HTMLTableCaptionElement { attribute DOMString align; };
The align IDL
  attribute of the caption element must
  reflect the content attribute of the same name.
[Supplemental] 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.
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.
[Supplemental] interface HTMLDivElement { attribute DOMString align; };
The align IDL
  attribute of the div element must reflect
  the content attribute of the same name.
[Supplemental] interface HTMLDListElement { attribute boolean compact; };
The compact IDL
  attribute of the dl element must reflect
  the content attribute of the same name.
[Supplemental] 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 { 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.
[Supplemental] interface HTMLHeadingElement { attribute DOMString align; };
The align IDL
  attribute of the h1–h6 elements must
  reflect the content attribute of the same name.
[Supplemental] interface HTMLHeadElement { attribute DOMString profile; };
User agents should ignore the profile content attribute on
  head elements.
When the attribute would be used as a list of URLs identifying metadata profiles, the user agent should instead always assume that all known profiles apply to all pages, and should therefore apply the conventions of all known metadata profiles to the document, ignoring the value of the attribute.
When the attribute's value would be handled as a list of URLs to be dereferenced, the user agent must use the following steps:
Split on
   spaces the value of the profile attribute.
For each token that is successfully resolved, fetch the resulting absolute URL and apply the appropriate processing.
The profile IDL
  attribute of the head element must reflect
  the content attribute of the same name, as if the attribute's value
  was just a string. (In other words, the value is not resolved in any way on getting.)
[Supplemental] 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.
[Supplemental] interface HTMLHtmlElement { attribute DOMString version; };
The version IDL
  attribute of the html element must reflect
  the content attribute of the same name.
[Supplemental] interface HTMLIFrameElement { attribute DOMString align; attribute DOMString frameBorder; attribute DOMString longDesc; attribute DOMString marginHeight; attribute DOMString marginWidth; attribute DOMString scrolling; };
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 iframeborder content
  attribute.
The longDesc
  IDL attribute of the iframe element must
  reflect the element's longdesc content attribute.
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.
[Supplemental] interface HTMLImageElement { attribute DOMString name; attribute DOMString align; attribute DOMString border; attribute unsigned long hspace; attribute DOMString longDesc; attribute unsigned long vspace; };
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.
[Supplemental] 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.
[Supplemental] interface HTMLLegendElement { attribute DOMString align; };
The align IDL
  attribute of the legend element must reflect
  the content attribute of the same name.
[Supplemental] interface HTMLLIElement { attribute DOMString type; };
The type IDL
  attribute of the li element must reflect
  the content attribute of the same name.
[Supplemental] 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.
[Supplemental] interface HTMLMenuElement { attribute boolean compact; };
The compact IDL
  attribute of the menu element must reflect
  the content attribute of the same name.
[Supplemental] 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 recognises 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 recommended 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.
[Supplemental] interface HTMLObjectElement { attribute DOMString align; attribute DOMString archive; attribute DOMString border; attribute DOMString code; attribute DOMString codeBase; attribute DOMString codeType; attribute boolean declare; attribute unsigned long hspace; attribute DOMString standby; attribute unsigned long vspace; };
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.
The codeType IDL
  attribute of the object element must reflect
  the element's codetype content
  attribute.
[Supplemental] interface HTMLOListElement { attribute boolean compact; attribute DOMString type; };
The compact and
  type IDL attributes of
  the ol element must reflect the respective
  content attributes of the same name.
[Supplemental] interface HTMLParagraphElement { attribute DOMString align; };
The align IDL
  attribute of the p element must reflect
  the content attribute of the same name.
[Supplemental] 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.
[Supplemental] interface HTMLPreElement { attribute unsigned long width; };
The width IDL
  attribute of the pre element must reflect
  the content attribute of the same name.
[Supplemental] 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.
[Supplemental] interface HTMLTableElement { attribute DOMString align; attribute DOMString bgColor; attribute DOMString border; attribute DOMString cellPadding; attribute DOMString cellSpacing; attribute DOMString frame; attribute DOMString rules; attribute DOMString width; };
The align, border, frame, 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.
[Supplemental] 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.
[Supplemental] interface HTMLTableCellElement { attribute DOMString abbr; attribute DOMString align; attribute DOMString axis; attribute DOMString bgColor; attribute DOMString ch; attribute DOMString chOff; attribute DOMString height; attribute boolean noWrap; attribute DOMString vAlign; attribute DOMString width; };
The abbr, align, axis, height, and width IDL attributes of
  the td and th elements must
  reflect the respective content attributes of the same
  name.
The bgColor IDL
  attribute of the td and th elements must
  reflect the elements' bgcolor content attributes.
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.
[Supplemental] interface HTMLTableRowElement { attribute DOMString align; attribute DOMString bgColor; attribute DOMString ch; attribute DOMString chOff; attribute DOMString vAlign; };
The align IDL
  attribute of the tr element must reflect
  the content attribute of the same name.
The bgColor IDL
  attribute of the tr element must reflect
  the element's bgcolor content
  attribute.
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.
[Supplemental] 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.
The bgsound, isindex,
  multicol, nextid, rb, and
  spacer elements must use the
  HTMLUnknownElement interface.
[Supplemental] interface HTMLDocument { attribute DOMString fgColor; attribute DOMString bgColor; attribute DOMString linkColor; attribute DOMString vlinkColor; attribute DOMString alinkColor; readonly attribute HTMLCollection anchors; readonly attribute HTMLCollection applets; void clear(); 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 | 
| bgColor | bgcolor | 
| linkColor | link | 
| vLinkColor | vlink | 
| aLinkColor | alink | 
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()
  method 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 behaviors:
The user agent must act as if the ToBoolean() operator in
   JavaScript converts the object returned for all to the false value.
The user agent must act as if, for the purposes of the == and != operators in
   JavaScript, the object returned for all is equal to the undefined value.
The user agent must act such that the typeof operator in JavaScript returns the string
   undefined when applied to the object returned
   for all.
These requirements are a willful
  violation of the JavaScript specification current at the time
  of writing (ECMAScript edition 3). 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]