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.
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:
The presence of an obsolete permitted DOCTYPE in an HTML document.
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.
The presence of a maxlength attribute on an
   input element whose type attribute is in the
   Number state.
The presence of a size attribute on an
   input element whose type attribute is in the
   Number state.
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".
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.
hgroupTo 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.
isindexUse an explicit form and text field combination instead.
listingnextidUse GUIDs instead.
noembedplaintextUse the "text/plain" MIME type instead.
strikeUse del instead if the element is marking an edit, otherwise use s instead.
xmpUse pre and code instead, and escape "<" and "&" characters as "<" and "&" respectively.
basefontbigblinkcenterfontmarqueemulticolnobrspacerttUse 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 elementscharset on link elementsUse an HTTP Content-Type header on the linked resource instead.
coords on a elementsshape on a elementsmethods on a elementsmethods on link elementsUse the HTTP OPTIONS feature instead.
name on a elements (except as noted in the previous section)name on embed elementsname on img elementsname on option elementsUse the id attribute instead.
urn on a elementsurn on link elementsSpecify the preferred persistent identifier using the href attribute instead.
accept on form elementsUse the accept attribute directly on the input elements 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.
ismap on input elementsUnnecessary. 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 elementslowsrc on img elementsUse a progressive JPEG image (given in the src attribute),
   instead of using two separate images.
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. [DOM]
media on source elementsUse script to select the media resource(s) to use.
datapagesize on table elementsUnnecessary. Omit it altogether.
summary on table elementsUse one of the techniques for describing
   tables given in the table section
   instead.
axis on td and th elementsscope on td elementsUse 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 elementsdatafld on a, applet, button, div, fieldset, frame, iframe, img, input, label, legend, marquee, object, param, select, span, and textarea elementsdataformatas on button, div, input, label, legend, marquee, object, option, select, span, and table elementsUse script and a mechanism such as XMLHttpRequest to populate the page dynamically. [XHR]
alink on body elementsbgcolor on body elementslink on body elementsmarginbottom on body elementsmarginheight on body elementsmarginleft on body elementsmarginright on body elementsmargintop on body elementsmarginwidth 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 elementshspace on embed elementsvspace on embed elementsalign on hr elementscolor on hr elementsnoshade on hr elementssize on hr elementswidth on hr elementsalign on h1—h6 elementsalign on iframe elementsallowtransparency on iframe elementsframeborder on iframe elementshspace on iframe elementsmarginheight on iframe elementsmarginwidth on iframe elementsscrolling on iframe elementsvspace on iframe elementsalign on input elementshspace on input elementsvspace 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 elementsalign on p elementswidth on pre elementsalign on table elementsbgcolor on table elementsbordercolor 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 elementsbackground on body, table, thead, tbody, tfoot, tr, td, and th elementsUse 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.
applet elementThe 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:
Document.Document is not fully active.Document's active sandboxing flag
   set has its sandboxed plugins browsing context flag set.object element that is not showing its
   fallback content.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.
marquee elementThe 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:
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, 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 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.
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:
src attribute specified, and the
   user agent is processing the frame's attributes for the first timeQueue a task to fire a simple event named load at the frame element.
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.
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 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.
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 shape; };
The coords, charset, name, 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 target; };
The charset 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 behavior 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 align; 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 behavior 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
  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 compares as equal to the undefined and
   null values. (Comparisons using the === operator, and
   comparisons to other values such as strings or objects, are unaffected.)
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 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.