manakai's Conformance Checking Guideline for Obsolete HTML Elements and Attributes

The manakai project, 18 April 2018

Latest version
https://manakai.github.io/spec-obsvocab/
Version history
https://github.com/manakai/spec-obsvocab/commits/gh-pages

Abstract

This specification defines authors' requirements for historical HTML elements and attributes, which are not defined in the HTML Standard or listed but marked as obsolete, such that conformance checkers can find authoring errors against these requirements. Use of such non‐conforming elements and attributes are sometimes necessary for compatibility with legacy or Galápagos user agents and/or historical authoring practices. A conformance checker that reports a non‐conforming elements and attributes just as non‐conforming is not useful enough to ease authoring processes in such legacy circumstances. The scope of this specification is explicitly limited to the conformance checking of documents (or parts of documents) that contains obsolete elements and attributes for the purpose of comaptibility.

This specification is developed as part of the manakai project. Although it might be useful to other parties, the only intended audiences of this specification are contributors of the project. This specification does not define or describe any kind of standard.

Status of this document

This section describes the status of this document at the time of its publication. Other documents might supersede this document.

This document is a technical specification, produced as part of the manakai project. It might be updated, replaced, or obsoleted by other documents at any time.

Comments on this document are welcome and may be sent to the author.

Translations of thie document might be available. The English version of the document is the only normative version.

Table of contents

  1. 1 Introduction
    1. 1.1 How requirements for non‐conforming elements and attributes are defined
    2. 1.2 Stability of this document
  2. 2 Common infrastructure
    1. 2.1 Terminology
    2. 2.2 Namespaces
  3. 3 Obsolete HTML elements and attributes
    1. 3.1 Metadata
    2. 3.2 Flow content
      1. 3.2.1 Lists
      2. 3.2.2 Tables
      3. 3.2.3 The marquee element
    3. 3.3 Boxes
      1. 3.3.1 Dimension
      2. 3.3.2 Margin and padding
      3. 3.3.3 Borders
      4. 3.3.4 Overflow
    4. 3.4 Background images and colors
    5. 3.5 Alignments
    6. 3.6 Line breaks
    7. 3.7 Phrasing content
      1. 3.7.1 The font element
    8. 3.8 Hyperlinks
    9. 3.9 Embedded content
      1. 3.9.1 The img element
        1. 3.9.1.1 Image sources
      2. 3.9.2 The embed element
      3. 3.9.3 The object and param elements
      4. 3.9.4 Audio and video
    10. 3.10 Frames
      1. 3.10.1 The frameset element
      2. 3.10.2 The frame element
      3. 3.10.3 Frame borders
      4. 3.10.4 The noframes element
    11. 3.11 Scripting
    12. 3.12 Forms
      1. 3.12.1 Autocomplete
    13. 3.13 User interaction
  4. 4 Elements and attributes not included in this specification
  5. 5 Machine-readable data
  6. Index
  7. References
    1. Normative references
    2. Non-normative references
  8. Author

1 Introduction

This section is non‐normative.

The HTML Standard defines the language vocabulary of HTML, i.e. a set of conforming HTML elements and attributes. Any other HTML elements and attributes are non‐conforming unless otherwise defined by some applicable specification. In particular, the HTML Standard identifies a number of non‐conforming elements and attributes as obsolete. It does not define any specific conformance requirement for such elements and attributes, as the use of them is by definition non-conforming.

However, authors are sometimes forced to use such non‐conforming elements and attributes, for compatibility with legacy user agents and/or historical authoring practices. A conformance checker that reports a non-conforming elements and attributes just as non-conforming is not useful enough to ease authoring processes in such legacy circumstances.

This specification defines authors' requirements for HTML elements and attributes not defined in the HTML Standard or those marked as obsolete, such that conformance checkers can find authoring errors against these requirements. The scope of this specification is explicitly limited to the conformance checking of documents (or parts of documents) that contains obsolete elements and attributes for the purpose of comaptibility. Elements and attributes conforming to these requirements are still non‐conforming. Especially, this specification cannot be an applicable specification in the context of the HTML Standard for the purpose of authors' requirements.

This specification is developed as part of the manakai project. Although it might be useful to other parties, the only intended audiences of this specification are contributors of the project. This specification does not define or describe any kind of standard.

1.1 How requirements for non‐conforming elements and attributes are defined

As a general rule, requirements for non‐conforming elements and attributes are derived by the following rules:

  1. If an element or attribute a is defined in a historical standard specification:
    • If the HTML Standard defines user agent requirements for a, author requirements for a should be derived from them.
    • Otherwise, if there is an element or attribute b that shares the definition or requirements with a in the specification, and b is defined in the HTML Standard, then b should share the same requirements as a's in the HTML Standard.
    • Otherwise, a's expected syntax in the specification should be used as requirements.
  2. Otherwise, if a is described in the first implementor's official reference documentation, a best effort attempt should be made to formalize a's expected usage documented there as requirements.

If an attribute maps to the pixel length property, the attribute value has to be a valid non-negative integer.

If an attribute maps to the dimension property, the attribute value has to be a valid dimension value.

1.2 Stability of this document

This document is a Living Standard. That is, requirements in this document could be modified at any time. Earlier revisions of this document is available from the version history page.

Requirements in this document might be modified in future revisions, sometimes incompatibly, in ways including but not limited to:

Support for non-standard extensions implemented by Japanese mobile phones (garakei) are dropped in .

The autocapitalize attribute is now defined by the HTML Standard.

2 Common infrastructure

This specification depends on the Infra Standard.

2.1 Terminology

The term HTML namespace is defined by the Infra Standard.

Terms applicable specifications, ASCII case-insensitive, HTML elements, XML documents, home subtree, valid integer, valid non-negative integer, set of comma-separated tokens, set of space-separated tokens, unordered set of unique space-separated tokens, valid browsing context name, valid browsing context name or keyword, boolean attribute, enumerated attribute, valid hash-name reference, event handler content attributes, content model, nothing, text, MIME type, valid MIME type, XML MIME type, URL, valid URL potentially surrounded by spaces, valid non-empty URL, valid non-empty URL potentially surrounded by spaces, absolute URL, resolve a URL, valid e-mail address, maps to the pixel length property, and maps to the dimension property are defined by the HTML Standard.

The term valid dimension value is defined in a commented out paragraph of the HTML Standard.

A string is a valid BCP 47 language tag if it is a valid language tag as defined by the IETF Language Tag specification [BCP47].

2.2 Namespaces

Except where otherwise stated, all elements defined or mentioned in this specification are in the HTML namespace, and all attributes deinfed or mentioned in this specification have no namespace.

3 Obsolete HTML elements and attributes

3.1 Metadata

If the version attribute of an html element is present, its value MAY be any string.

If the http-equiv attribute of a meta element is in the content-language state, the content attribute value MUST be a valid BCP 47 language tag.

If the http-equiv attribute of a meta element is in the cookie state, the content attribute value MUST be a set-cookie-string [COOKIES]. For the purpose of validation of this attribute value, the character set of the ABNF production rule of the set-cookie-string is Unicode.

The content model of the basefont element is nothing.

If the scheme attribute of the meta element is present, its value MAY be any string.

The content model of the bgsound element is nothing.

If the prefix attribute of an html or head element is specified, it value MUST be one of these values:

The property attribute might be used as part of OGP.

3.2 Flow content

The content model of the center element is same as the div element.

The content model of xmp, listing, and plaintext elements are text.

3.2.1 Lists

The content model of the dir element, including the content model of the child li elements of the elements, is same as the ul element.

If the type attribute of a ul element is present, its value MUST be equal to one of disc, circle, and square, ASCII case-insensitively. If the type attribute of an li element is present, its value MUST be one of values allowed for type attributes of ul and ol elements.

The compact attribute of the dir, dl, menu, ol, or ul element is a boolean attribute.

3.2.2 Tables

If the abbr attribute of a td element is present, its value MUST be a syntactically valid value of the abbr attribute of the th element.

If the axis attribute of a td or th element is present, its value MAY be any string.

If the scope attribute of a td element is present, its value MUST be a syntactically valid value of the scope attribute of the th element.

3.2.3 The marquee element

The content model of the marquee element is same as the div element.

If the scrolldelay attribute of a marquee element is present, its value MUST be a valid non-negative integer.

If the scrollamount attribute of a marquee element is present, its value MUST be a valid non-negative integer.

If the loop attribute of a marquee element is present, its value MUST be a valid integer that represents −1 or an integer greater than 0.

Attributes behavior and direction of the marquee element are enumerated attributes. Attribute truespeed of the marquee element is a boolean attribute.

The following attributes of the marquee element are event handler content attributes: onbounce, onfinish, and onstart.

3.3 Boxes

3.3.1 Dimension

If the height or width attribute of a table, td, th, or marquee element is specified, its value MUST be a valid non-negative integer.

The col element's width attribute value MUST be a valid non-negative integer.

The hr element's width attribute value MUST be a valid non-negative integer.

The tr element's height attribute value MUST be a valid non-negative integer.

If the width attribute of a colgroup element [HTML4] is present, its value MUST be a valid dimension value or an optional valid non-negative integer followed by a U+002A ASTERISK character (*).

The pre element's width attribute value MUST be a valid non-negative integer.

The hr element's size attribute value MUST be a valid non-negative integer.

3.3.2 Margin and padding

The body element's marginheight, marginwidth, topmargin, and rightmargin attribute values MUST be valid non-negative integers. The iframe and frame elements' marginheight and marginwidth attribute values MUST be valid non-negative integers.

The table element's cellspacing, cellpadding, and cellborder [SAFARI] attribute values MUST be valid non-negative integers.

If the hspace or vspace attribute of an embed, iframe, img, input, marquee, object, or table element is specified, its value MUST be a valid dimension value. The hspace and vspace attributes of the input element apply only to elements whoes type attribute is in the Image Button state.

The units attribute of the embed element [DEVEDGE] [MSDN] is an enumerated attribute with keywords pixels, px, en, and em.

3.3.3 Borders

The rules attribute of a table element is an enumerated attribute with keywords none, groups, rows, cols, and all.

The frame attribute of a table element is an enumerated attribute with keywords void, above, below, hsides, lhs, rhs, vsides, box, and border.

The table element's border attribute value MUST either be the empty string or the value 1.

The table element's tableborder attribute value [SAFARI] MUST be a valid non-negative integer.

If the border attribute of an embed [DEVEDGE], img, or object element, or an input element whose type attribute is in the Image Button state is specified, its value MUST be a valid non-negative integer.

The hr element's noshade attribute is a boolean attribute.

3.3.4 Overflow

The scrolling attribute of a frame or iframe element is an enumerated attribute with keywords on, scroll, yes, off, noscroll, no, and auto. Keywords other than yes, no, and auto are non‐ conforming.

3.4 Background images and colors

The body, table, thead, tbody, tfoot, tr, td, and th elements' background attribute values MUST be valid non-empty URLs potentially surrounded by spaces.

A valid legacy color value is either a U+0023 NUMBER SIGN character (#) followed by six (6) characters in the range U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9), U+0041 LATIN CAPITAL LETTER A to U+0046 LATIN CAPITAL LETTER F, and U+0061 LATIN SMALL LETTER A to U+0066 LATIN SMALL LETTER F, or a string that ASCII case-insensitively matches to one of the keywords listed in the SVG color keywords section of the CSS Color specification [CSSCOLOR].

The body, table, thead, tbody, tfoot, tr, td, th, and marquee elements' bgcolor attribute values MUST be valid legacy color values.

The body element's text, link, vlink, and alink attribute values MUST be valid legacy color values.

The table, tr [MSDN], td [MSDN], and th [MSDN] elements' bordercolor attribute values MUST be valid legacy color values. The table, tr, td, and th elements' bordercolordark and bordercolorlight attribute values [MSDN] MUST be valid legacy color values.

The color attribute value of the font element, if present, MUST be a valid legacy color value.

The hr element's color attribute value MUST be a valid legacy color value.

The allowtransparency attribute of frame and iframe element [MSDN] is an enumerated attribute with keywords true and false.

The application attribute of frame and iframe element [MSDN] is an enumerated attribute with keywords yes and no.

The bgproperties attribute of the body element [MSDN] is an enumerated attribute with two keywords: fixed and the empty string.

3.5 Alignments

The align attribute of a table element is an enumerated attribute with keywords left, right, center, middle, abscenter, and absmiddle. Keywords middle, abscenter, and absmiddle are non‐ conforming.

The align attribute of a caption element is an enumerated attribute with keywords left, right, top, and bottom,

The align attribute of a legend element is an enumerated attribute with keywords left, right, and center.

The align attribute of elements div, h1, h2, h3, h4, h5, h6, and p, is an enumerated attribute with keywords left, right, center, and justify.

The align attribute of a hr element is an enumerated attribute with keywords left, right, and center.

The align attribute of a col, colgroup [HTML4], thead, tbody, tfoot, tr, th, or td element is an enumerated attribute with keywords left, center, middle, absmiddle, right, justify, and char, where middle and absmiddle are non-conforming.

The align attribute of an embed, iframe, img, input, or object element is an enumerated attribute with keywords left, right, top, bottom, baseline, center, middle, texttop, absmiddle, abscenter. Keywords other than left, right, top, middle, and bottom are non-conforming. The align attribute of the input element applies only to input elements whose type attribute is in the Image Button state.

The valign attribute of a col, colgroup [HTML4], thead, tbody, tfoot, tr, th, or td attribute is an enumerated attribute with keywords top, middle, bottom, and baseline.

The valign attribute of a caption element [MSDN] is an enumerated attribute with keywords top and bottom.

If the char attribute of a col, colgroup [HTML4], thead, tbody, tfoot, tr, th, or td element is present, its value MUST be a string whose length is one (1), i.e. a character.

If the charoff attribute of a col, colgroup [HTML4], thead, tbody, tfoot, tr, th, or td element is present, its value MUST be a valid dimension value.

3.6 Line breaks

The nowrap attribute of body, dt, dd, and div elements [MSDN], as well as of td and th elements, is a boolean attribute.

The wrap attribute of the pre element is a boolean attribute.

The clear attribute of the br element and address, blockquote, center, h1, h2, h3, h4, h5, h6, listing, p, plaintext, pre, and xmp elements [MSDN] is an enumerated attribute with keywords none, left, right, all, and both, where both is non-conforming.

3.7 Phrasing content

The content model of acronym, big, blink, nobr, strike, and tt elements are same as the span element.

3.7.1 The font element

Content model of the font element is transparent.

If the face attribute of a font element is present, its value MAY be any string.

If the size attribute of a font element is present, its value MUST be an optional U+002B PLUS SIGN character (+) or an optional U+002D HYPHEN-MINUS character (-), followed by a character in the range U+0031 DIGIT ONE (1) to U+0037 DIGIT SEVEN (7).

3.8 Hyperlinks

A valid hash-ID reference to an element of type type is a string consisting of a U+0023 NUMBER SIGN character (#) followed by a string which exactly matches the ID of an element with type type in the same home subtree.

The x-ms-format-detection attribute of HTML elements [MSDN] is enumerated attribute with keywords all, none, and phone.

The nohref attribute of the area element is a boolean attribute.

If the charset attribute of an a or link element is present, its value MUST be a label. The term label is defined by the Encoding Standard.

If the coords attribute and/or the shape attribute of an a element is present, their values, and their presence themselves, MUST be valid if they were specified for an area element with appropriate href and alt attributes specified.

3.9 Embedded content

If there are embed, and/or img elements with their name attributes specified, those elements MUST be treated as if they were a elements for the purpose of conformance of name attributes of a, embed, and img elements in the document, except that use of the name attributes for these elements are always non-conforming. (Use of the name attribute for the a element is sometimes obsolete but conforming according to HTML Standard.)

3.9.1 The img element

If the usemap attribute of the input element is present, its value MUST be a valid hash-name reference to a map element. The usemap attribute of the input element applies only to input elements whose type attribute is in the Image Button state.

If the longdesc attribute of the frame, iframe, or img element is present, its value MUST be a valid URL potentially surrounded by spaces.

The composite attribute of the img element [SAFARI] is a enumerated attribute with the keyword source-over.

3.9.1.1 Image sources

If the dynsrc [MSDN], lowsrc [DEVEDGE] [MSDN], or vrml [MSDN] attribute of the img or input element is present, its value MUST be a valid non-empty URL potentially surrounded by spaces. The dynsrc, lowsrc, or vrml attribute of the input element applies only to input elements whose type attribute is in the Image Button state.

If the oversrc [SAFARI] attribute of the img element is present, its value MUST be a valid non-empty URL potentially surrounded by spaces.

3.9.2 The embed element

If the pluginpage [SAFARI], pluginspage, or pluginurl attribute of the embed element [DEVEDGE] is present, its value MUST be a valid URL potentially surrounded by spaces.


The content model of the noembed element is text.

3.9.3 The object and param elements

If the archive attribute of the object element is present, its value MUST be a set of space-separated tokens, each of which MUST be a valid non-empty URL.

When a URL specified within the archive attribute of the object element is resolved, the URL obtained by resolving the value of the codebase attribute of the element, if any, MUST be used as the base URL.

If the classid attribute of an object element is present, its value MUST be a valid non-empty URL potentially surrounded by spaces and MUST be an absolute URL.

If the code attribute of an embed [SAFARI], or object element is present, its MUST be a valid non-empty URL potentially surrounded by spaces.

If the codebase attribute of an object element is present, its MUST be a valid non-empty URL potentially surrounded by spaces.

If the codetype attribute of an object element is present, its MUST be a valid MIME type. This attribute SHOULD be presented if the element has a classid attribute.


The declare attribute of the object element is a boolean attribute.

If the standby attribute of the object element is present, its value MAY be any string.

The palette attribute of the embed element [DEVEDGE] is an enumerated attribute with keywords foreground and background.


If the type attribute of a param element is present, its value MUST be a valid MIME type.

The valuetype attribute of a param element is an enumerated attribute with keywords data, ref, and object.

3.9.4 Audio and video

The start attribute of the img or input element [MSDN] is an enumerated attribute with keywords fileopen and mouseover. The start attribute of the input element applies only to input elements whose type attribute is in the Image Button state. The attribute MUST NOT be specified unless the element also has the dynsrc attribute specified.

3.10 Frames

3.10.1 The frameset element

The content model of the frameset element is one or more frame or frameset elements. Additionally, there can be a noframes element in some case.


A valid list of dimensions is a set of comma-separated tokens, each of which MUST be one of a valid dimension value, an optional valid non-negative integer followed by a U+002A ASTERISK character (*), or a U+002A ASTERISK character (*).

If the cols or rows attribute of a frameset element is present, its value MUST be a valid list of dimensions.

3.10.2 The frame element

The content model of the frame element is nothing.

If the src attribute of a frame element is present, its value MUST be a valid non-empty URL potentially surrounded by spaces.

If the name attribute of a frame element is present, its value MUST be a valid browsing context name.

The noresize attribute of frame and iframe elements [MSDN] is boolean attributes.

3.10.3 Frame borders

The frameborder attribute of a frame, frameset, iframe, or embed [DEVEDGE] element is an enumerated attribute, with keywords 1, yes, 0, and no, where keywords yes and no are non‐conforming.

If the border attribute of a frameset [DEVEDGE] or iframe element [MSDN] is present, its value MUST be a valid non-negative integer.

The frame and frameset elements' bordercolor attribute values MUST be valid legacy color values.

If the framespacing attribute of frame, frameset, or iframe element [MSDN] is present, its value MUST be a valid non-negative integer.

3.10.4 The noframes element

The content model of the noframes element is text.

The noframes element MAY be used as a child of the frameset element. However, it MUST NOT have more than one ancestor frameset elements.

3.11 Scripting

If the for attribute of a script element is present, its value MUST be the ID of an element in the same home subtree.

If the event attribute of a script element is present, its value MAY be any string.


The following attributes of HTML elements [MSDN] MUST be treated as event handler content attributes: onactivate, onafterupdate, onbeforeactivate, onbeforecopy, onbeforecut, onbeforedeactivate, onbeforeeditfocus, onbeforepaste, onbeforeupdate, oncellchange, oncontrolselect, ondataavailable, ondatasetchanged, ondatasetcomplete, ondeactivate, onerrorupdate, onfilterchange, onfocusin, onfocusout, onhelp, onlayoutcomplete, onlosecapture, onmouseenter, onmouseleave, onmove, onmoveend, onmovestart, onpropertychange, onresizeend, onresizestart, onrowenter, onrowexit, onrowsdelete, onrowsinserted, and onselectstart.

The following attributes of HTML elements [SAFARI] MUST be treated as event handler content attributes: ongesturechange, ongestureend, ongesturestart, onorientationchange, onsearch, ontouchcancel, ontouchend, ontouchmove, and ontouchstart.

3.12 Forms

If this specification says an attribute applies to certain states of input or button elements, the attribute MUST NOT be specified unless the attribute applies to the element.

The wrap attribute of a textarea element, for the purpose of conformance checking, MUST be treated as if there are additional keywords: off, virtual, and physical. However, these keywords are non‐conforming.

The autocorrect attribute of the input and textarea elements [SAFARI] are enumerated attribute with keywords on and off. The autocorrect attribute of the input element applies only to input elements whose type attribute is in the Text, Search, URL, E-mail, Telephone, or Password state.

The content model of the keygen element is nothing.

If the precision attribute of an input element [SAFARI] is present, its value MUST be given in one of the following forms: one or more of characters in the range U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9), followed by keyword dp or sf, keyword integer, or keyword float. The precision attribute of the input element applies only to input elements whose type attribute is in the Number or Range state.

3.12.1 Autocomplete

If the autosave attribute of an input element [SAFARI] is present, its value MAY be any string. The autosave attribute of the input element applies only to input elements whose type attribute is in the Search state.

The incremental attribute of an input element [SAFARI] is a boolean attribute. The incremental attribute of the input element applies only to input elements whose type attribute is in the Search state.

If the results attribute of an input element [SAFARI] is present, its value MUST be a valid non-negative integer. The results attribute of the input element applies only to input elements whose type attribute is in the Search state.

The vcard_name attribute of the input element is an enumerated attribute with keywords vCard.Business.City, vCard.Business.Country, vCard.Business.Fax, vCard.Business.Phone, vCard.Business.State, vCard.Business.StreetAddress, vCard.Business.URL, vCard.Business.Zipcode, vCard.Cellular, vCard.Company, vCard.Department, vCard.DisplayName, vCard.Email, vCard.FirstName, vCard.Gender, vCard.Home.City, vCard.Home.Country, vCard.Home.Fax, vCard.Home.Phone, vCard.Home.State, vCard.Home.StreetAddress, vCard.Home.Zipcode, vCard.Homepage, vCard.JobTitle, vCard.LastName, vCard.MiddleName, vCard.Notes, vCard.Office, and vCard.Pager. The vcard_name attribute of the input element applies only to input elements whose type attribute is in the Text, Search, Password, URL, E-mail, or Telephone state.

3.13 User interaction

The atomicselection attribute of an HTML element [MSDN] is an enumerated attribute with keywords true and false.

The hidefocus attribute of an HTML element [MSDN] is a boolean attribute.

The unselectable attribute of an HTML element [MSDN] is an enumerated attribute with keywords on and off.

The disabled attribute of an HTML element [MSDN] is a boolean attribute.

The HTML Standard defines the (conforming) disabled attribute for several HTML elements. This requirement does not (or in fact cannot) override it in any way.

4 Elements and attributes not included in this specification

This section is non-normative.

Following features are not included in this specification, as they are not implemented by current Web browsers such that checking against them in validators will not help anyone:

Some of features listed in this section were defined in this specification but dropped as described in an earlier section.

This section does not intend to enumerate all obsolete HTML features. A JSON data file in the data-web-defs repository (documentation) is trying to list any known obsolete HTML elements and attributes.

5 Machine-readable data

This section is non-normative.

Some of data for elements and attributes in this specification are available as JSON data in the data-web-defs repository (documentation).

Test data for validators are also available in the tests-web repository.

Index

This section is non-normative.

Common attributes of HTML elements
atomicselection
disabled
hidefocus
onactivate
onafterupdate
onbeforeactivate
onbeforecopy
onbeforecut
onbeforedeactivate
onbeforeeditfocus
onbeforepaste
onbeforeupdate
oncellchange
oncontrolselect
ondataavailable
ondatasetchanged
ondatasetcomplete
ondeactivate
onerrorupdate
onfilterchange
onfocusin
onfocusout
ongesturechange
ongestureend
ongesturestart
onhelp
onlayoutcomplete
onlosecapture
onmouseenter
onmouseleave
onmove
onmoveend
onmovestart
onorientationchange
onpropertychange
onresizeend
onresizestart
onrowenter
onrowexit
onrowsdelete
onrowsinserted
onselectstart
onsearch
ontouchcancel
ontouchend
ontouchmove
ontouchstart
unselectable
x-ms-format-detection
The a element
charset
coords
shape
The acronym element
No element-specific attribute.
The address element
clear
The area element
nohref
The basefont element
No element-specific attribute.
The bgsound element
No element-specific attribute.
The big element
No element-specific attribute.
The blink element
No element-specific attribute.
The body element
alink
background
bgcolor
bgproperties
link
marginheight
marginwidth
nowrap
rightmargin
text
topmargin
vlink
The br element
clear
The caption element
align
valign
The center element
clear
The col element
align
char
charoff
valign
width
The colgroup element
align
char
charoff
valign
width
The dd element
nowrap
The dir element
compact
The div element
align
nowrap
The dl element
compact
The dt element
nowrap
The embed element
align
border
code
hspace
name
palette
pluginpage
pluginspage
pluginurl
units
vspace
The font element
color
face
size
The frame element
allowtransparency
application
bordercolor
frameborder
framespacing
longdesc
marginheight
marginwidth
name
noresize
scrolling
src
The frameset element
cols
border
bordercolor
frameborder
framespacing
rows
The h1 element
align
clear
The h2 element
align
clear
The h3 element
align
clear
The h4 element
align
clear
The h5 element
align
clear
The h6 element
align
clear
The head element
prefix
The hr element
align
color
noshade
size
width
The html element
prefix
version
The iframe element
align
allowtransparency
application
border
frameborder
framespacing
hspace
longdesc
marginheight
marginwidth
noresize
scrolling
vspace
The img element
align
border
composite
dynsrc
hspace
localsrc
longdesc
lowsrc
name
oversrc
start
vrml
vspace
The input element's attributes
align
autocorrect
autosave
border
dynsrc
hspace
incremental
lowsrc
precision
results
start
usemap
vcard_name
vrml
vspace
The keygen element
No element-specific attribute.
The legend element
align
The li element
type
The link element
charset
The listing element
clear
The marquee element
behavior
direction
height
hspace
loop
onbounce
onfinish
onstart
scrollamount
scrolldelay
truespeed
vspace
width
The menu element
compact
The meta element
scheme
The nobr element
No element-specific attribute.
The noembed element
No element-specific attribute.
The noframes element
No element-specific attribute.
The object element
align
archive
border
classid
code
codebase
codetype
declare
hspace
standby
vspace
The ol element
compact
The p element
align
clear
The param element
type
valuetype
The plaintext element
clear
The pre element
clear
width
wrap
The script element
event
for
The strike element
No element-specific attribute.
The table element
align
background
bgcolor
border
bordercolor
bordercolordark
bordercolorlight
cellborder
cellpadding
cellspacing
frame
height
hspace
rules
tableborder
vspace
width
The tbody element
align
background
bgcolor
char
charoff
valign
The td element
align
abbr
axis
background
bgcolor
bordercolor
bordercolordark
bordercolorlight
char
charoff
height
nowrap
scope
valign
width
The textarea element
autocorrect
The tfoot element
align
background
bgcolor
char
charoff
valign
The th element
align
axis
background
bgcolor
bordercolor
bordercolordark
bordercolorlight
char
charoff
height
nowrap
valign
width
The thead element
align
background
bgcolor
char
charoff
valign
The tr element
align
background
bgcolor
bordercolor
bordercolordark
bordercolorlight
char
charoff
height
valign
The tt element
No element-specific attribute.
The ul element
compact
type
The xmp element
clear

References

Normative references

BCP47
Tags for Identifying Languages; Matching of Language Tags, A. Phillips, M. Davis. IETF BCP 47.
COOKIES
HTTP State Management Mechanism, A. Barth. IETF RFC 6265.
CSSCOLOR
CSS Color Module Level 3, Tantek Çelik, Chris Lilley, L. David Baron. W3C Editor's Draft.

Non-normative references

ACCESS
XHTML Access Module, Mark Birbeck, Shane McCarron, Steven Pemberton, T. V. Raman, Richard Schwerdtfeger, W3C Editor's Draft, .
DEVEDGE
HTML Tag Reference, netscape devedge, Netscape, .
HTML20
Hypertext Markup Language - 2.0, Tim Berners-Lee, Daniel W. Connolly, RFC 1866, IETF Proposed Standard (obsolete), November 1995.
HTML2x
Internationalization of the Hypertext Markup Language, Frangois Yergeau, Gavin Thomas Nicol, Glenn Adams, Martin J. Dürst, RFC 2070, IETF Proposed Standard (obsolete), January 1997.
HTML30
HyperText Markup Language Specification Version 3.0, David Raggett, March 1995.
HTML4
HTML 4.01 Specification, Dave Raggett, Arnaud Le Hors, Ian Jacobs, W3C Recommendation, .
HTMLPLUS
A Review of the HTML+ Document Format, David Raggett.
M12N11
XHTMLTM Modularization 1.1, Daniel Austin, Subramanian Peruvemba, Shane McCarron, Masayasu Ishikawa, Mark Birbeck, W3C Proposed Edited Recommendation, .
MDC
HTML - MDC, Mozilla Developer Center (MDC).
MSDN
HTML and CSS, Microsoft Developer Network (msdn).
RFC1942
HTML Tables, Dave Raggett, RFC 1942, IETF Experimental RFC (obsolete), May 1996.
RFC2659
Security Extensions For HTML, Eric Rescorla, Allan M. Schiffman, RFC 2659, IETF Experimental RFC, August 1999.
RDFA
RDFa in XHTML: Syntax and Processing, Ben Adida, Mark Birbeck, Shane McCarron, Steven Pemberton, W3C Recommendation, .
ROLE
XHTML Role Attribute Module, Mark Birbeck, Shane McCarron, Steven Pemberton, T. V. Raman, Richard Schwerdtfeger, W3C Editor's Draft, .
RUBY
Ruby Annotation, Marcin Sawicki, Michel Suignard, 石川雅康, Martin Dürst, Tex Texin, W3C Recommendation, .
SAFARI
Safari HTML Reference, Apple, .
WF2
Web Forms 2.0, Ian Hickson, WHATWG Working Draft (superceded), .
XHTML2
XHTMLTM 2.0, Jonny Axelsson, Mark Birbeck, Micah Dubinko, Beth Epperson, Masayasu Ishikawa, Shane McCarron, Ann Navarro, Steven Pemberton, W3C Working Draft, .
XHTML2ED
XHTMLTM 2.0, Jonny Axelsson, Mark Birbeck, Micah Dubinko, Beth Epperson, Masayasu Ishikawa, Shane McCarron, Ann Navarro, Steven Pemberton, W3C Editor's Draft, .
XHTMLRDFA11
XHTML+RDFa 1.1, Shane McCarron, W3C Recommendation, .

Author

This document is written by Wakaba <wakaba@suikawiki.org>.

This document is developed as part of the the manakai project.

Per CC0, to the extent possible under law, the author has waived all copyright and related or neighboring rights to this work.