Complete table of HTML, XHTML and WML support

HTML 4.01, XHTML 1.0 and XHTML 1.1

Opera supports HTML 4.01, XHTML 1.0 and XHTML 1.1 with these exceptions:

• The longdesc attribute of the img element is not supported.
• Event attributes are not supported for the option element.
• The col width attribute does not support multilengths.
• The object standby and declare attributes are not supported.
• The table cell attributes char and charoff are not supported.
• The defer="" attribute on script elements is not supported.
• The basefont element is not supported.
• Ruby annotations are not supported.

Opera uses the HTML parser for text/html resources and the XML parser for resources with a XML MIME-type such as application/xhtml+xml. Please note that namespaces are not supported for text/html; this practice was discontinued with the release of Opera 9.

HTML 5 (a draft in development)

Opera 9.5 adds support for the next version of HTML - HTML 5. Note that HTML 5 is a work in progress, thus changes to the draft specification may be made at any time. Respectively, Opera considers its implementations for HTML 5 experimental until its specification has stabilized. Support is provided for the following:

• <canvas> element/API
• contenteditable attribute
• designMode DOM attribute
• innerHTML
• getElementsByClassName
• embed element
• Audio object
• Cross-document messaging
• Server-sent DOM events

Web Forms 2.0

Opera has experimental support for Web Forms 2.0. Web Forms 2.0 is a work in progress.

XHTML Basic

Opera supports XHTML Basic with the following exceptions:

• The object standby, declare attributes are not supported.
• The inputmode attribute is supported; however,
  • its implementation is platform-dependant
  • it is not enabled by default
  • it is not in the Opera 9.5 Desktop version

OMA XHTML Mobile Profile

Opera supports the XHTML Mobile Profile 1.0 and 1.1 and extensions to XHTML Basic with no exceptions.

• It supports XHTML Mobile Profile 1.2 with the exception of the declare attribute of object.

XHTML+Voice (X+V)

With the IBM Voice component, Opera fully supports the XHTML+Voice profile 1.2 (and the Mobile Profile subset).

• The support of X+V includes support of CSS3 Speech (with an -xv- prefix as this module is under preparation).
• X+V needs to be served as an XML media type (application/xml, application/xhtml+xml, application/x-xhtml+voice+xml) for XML Events to take effect.
• For more information see the X+V developer documentation.

WML 1.3 and 2.0

Wireless Markup Language, versions 1.0 to 1.3 - while based on an HTML subset - must be considered a separate markup language for most practical purposes. WML 2.0 can better be considered an extension of XHTML Basic with WML 1.3 features. Opera supports WML 1.3 and 2.0 with the following exceptions:

• the columns attribute
• the input formatting code <lang:class>
• the wml:getvar element

Opera can parse and display XML documents.

• Opera can be both a validating and non-validating processor.
• Documents with Content-type text/xml, application/xml or with a subtype ending on +xml will be treated as an XML document.
• If a content-type is not available, the ".xml" file extension will also make the document be treated as XML.
• Opera does not use US-ASCII as the default character set for text/xml, but otherwise follows RFC3023.
• We recommend using application/xml instead of text/xml or use explicit character set declaration.

XSLT, XPath and XSL-FO

Opera supports XSLT 1.0 and XPath 1.0 with the following exceptions:

• The namespace-alias element is not supported.
• Opera does not support XSL-FO.

XML ID

Opera supports the xml:id attribute.

XML namespaces

Opera fully supports XML namespaces.

XML Events

Opera supports XML Events and it is used in SVG and X+V.

• HTML script and VoiceXML form can be handlers for XML Events.

XML SVG

Opera supports the XML <svg:handler> element. This element only executes its content when called from an XML Event listener.

XML and CSS

Opera allows CSS style sheets and XSLT transformation sheets to be linked to XML with an XML Processing instruction according to

• the W3C Recommendation "Associating Style Sheets with XML Documents"
• the HTTP Link: header proposed for standardization in the IETF

Here is a simple example:

<?xml version="1.0"?>
<?xml-stylesheet href="shakespeare.css" type="text/css"?>

If no style sheet is present and the page is not namespaced to HTML or SVG, Opera will use the initial values on all CSS properties to display the document. All elements will be inline, and all text will be rendered in the same font.

MathML for CSS profile

Opera 9.5 supports the current working draft of the MathML for CSS profile with the following exceptions:

• Radicals and some fences do not inherit text color from document.
• White space characters between token elements (mi, mn, mo, ms, mspace, mtext) are not discarded.
• class and style attributes are not supported.

The following tabular data table contains specific elements/attributes included in the profile:

Table of CSS support

CSS Level 1

Opera supports all of CSS1.

CSS Level 2

Opera supports CSS2 with the exception of these

• properties:
  • font-size-adjust
  • font-stretch
  • marker-offset
  • marks
• list style types:
  • cjk-ideographic
  • hebrew
  • hiragana
  • hiragana-iroha
  • katakana
  • katakana-iroha
• property/value combinations:
  • display: marker
  • text-align: <string>
  • visibility: collapse
• named pages (as described in section 13.3.2)
• the @font-face construct
• URI values for the cursor property
  • see section 18.1 Cursors: the 'cursor' property

CSS Level 2 Revision 1

CSS 2.1 is currently a W3C Candidate Recommendation.

• Its compliance is measured against the latest version, but the final recommendation may differ.
• Opera supports CSS2.1 with the exception of:
  • the visibility: collapse property value

CSS3 - proposed properties supported by Opera

Note that these properties are at an early stage of development and may be changed or removed from the specifications at any time. Use them on an experimental basis.

• selectors level 3
• the HSL color model
• partial support for Media Queries
• content applicable on all elements, not just on the :before and :after pseudo-elements
• box-sizing
• opacity
• overflow-x
• overflow-y
• text-shadow, including multiple shadows
• outline-offset
• currentColor
• -o-background-size
• -o-table-baseline
• -o-text-overflow
• nav-up, nav-right, nav-down, nav-left

CSS Mobile profile

Opera fully supports the CSS Mobile Profile 1.0. Note that the CSS Mobile Profile 2.0 is in draft stage and coinsidered a work in progress. For your guide, Opera support for the 2.0 Profile will be added to this document as it occurs.

WAP CSS

WAP CSS is an extension of the CSS Mobile Profile. Opera fully supports WCSS versions 1.0 and 1.1.

Opera's participation

WAI-ARIA is a proposal/work in progress. Opera participates in this working group which will ultimately release the WAI-ARIA specification. Please see the WAI-ARIA Working Draft for details.

Opera 9.5 supports parsing WAI-ARIA in HTML with the attributes in a null namespace ("in no namespace"), as per the latest decisions on WAI-ARIA at the time Opera 9.5 was released. This support is experimental, while the WAI-ARIA standard stabilizes.

Opera supports widgets and accordingly has produced the Opera Widgets SDK.

• Widgets are client-side Web applications that run on the user's desktop, mobile or other device.
• The Opera Widgets specification was submitted to the W3C and Widgets 1.0 is currently a W3C working draft.

• Complete table of ECMAScript support

ECMAScript is the standardized version of JavaScript Core. It is being standardized through the ECMA standards body. ECMAScript does not include browser and document related objects.

ECMA-262 2 and 3

Opera supports the entire ECMA-262 2nd and 3rd standards with no exceptions. They are more or less aligned with JavaScript 1.3/1.5 Core.

ECMAScript 3.x and 4

Opera is actively participating in ECMA TC39 which is involved with developing successors to the current specification. Opera will support future editions of the language as consensus is reached and the specs become finalized.

• Complete table of DOM 2 Core support
• Complete table of DOM 2 HTML Objects support
• Complete table of DOM 2 Events support
• Complete table of DOM 2 Style support
• Complete table of DOM SVG support
• Complete table of XMLHttpRequest support
• Complete table of <canvas> support

DOM 2 Core

Opera has full support for the fundamental interfaces of DOM 2 Core with minor exceptions. Opera does not support these extended interfaces:

• Notation
• Entity
• EntityReference

DOM 2 HTML

Opera has full support for DOM 2 HTML with minor exceptions corresponding to HTML support exceptions.

DOM 2 Events

Opera 9 has full support of DOM 2 Events with no exceptions.

• The work on DOM 3 Events has restarted at the W3C.
• We expect to have no exceptions when it becomes a recommendation.

DOM 2 Style

Opera supports DOM 2 Style with some exceptions.

• The CSS object model is under development in order to replace the existing DOM 2 style specification. Opera actively participates in this work, and we expect to support fully the new object model.

DOM 2 Range

Opera supports the DOM 2 Range.

DOM 2 Traversal

Opera supports DOM 2 Traversal, with some exceptions.

DOM 3 Element Traversal specification (Working Draft)

Opera supports the Element Traversal specification (Working Draft).

• The ElementTraversal interface allows script navigation of the elements of a DOM tree, excluding all other nodes in the DOM, such as text nodes.
• It also provides an attribute to expose the number of child elements of an element.

DOM 3 Load and Save

Opera supports Load and Save with some exceptions.

DOM 3 XPath

Opera supports DOM 3 XPath with the same exceptions as with XSLT.

• This DOM specification is currently a W3C note.

DOM SVG

Note: see the preceding DOM SVG table and also the SVG section in following Graphics support topic.

Opera supports DOM SVG with the following version 1.1 exceptions:

• SVGAltGlyphDefElement
• SVGAltGlyphElement
• SVGAltGlyphItemElement
• SVGCSSRule
• SVGColorProfileElement
• SVGColorProfileRule
• vSVGCursorElement
• SVGEvent
• SVGExternalResourcesRequired
• SVGGlyphRefElement
• SVGICCColor (no ICC color support)
• SVGLangSpace
• SVGRenderingIntent
• SVGViewSpec
• SVGZoomEvent

XMLHttpRequest (XHR)

Opera actively participates in the W3C Web Applications Working Group, which is repsonsible for XMLHttpRequest specification. The XMLHttpRequest specification is in draft status as of the release date of Opera 9.5. We expect to support it fully when it becomes a recommendation.

<canvas>

Opera supports the <canvas> element specification, which is currently a work in progress.

Protocols

Opera has full support for HTTP 1.0 and HTTP 1.1. Highlights include the following

• Persistent connections (multiple request/response through one connection)
• Cache-Control
  • no-cache (always check for fresh document)
  • no-store (do not save to disk)
  • must-revalidate (only for HTTPS pages, which indicates that the document should be revalidated during history navigation)
• Basic Authentication (passwords)
  • Supports Digest Authentication, excepting integrity check on body.
• Resume download, provided the server supports it
• SSL, TLS support (also through proxy/firewall)
• Proxy for HTTP, FTP, Gopher and WAIS
• HTTP upload of files is supported.

Encryption

Opera supports 128 and 256 bit encryption (RSA, DSA and DH key exchange methods) for the Secure Sockets Layer (SSL) version 3, and the successor Transport Layer Security (TLS) 1.0 and 1.1.

• This is supported for HTTP (Web), IRC (chat), NNTP (news), POP and SMTP (e-mail).
• Note: SSL 2 is obsolete and no longer supported.
• Support for generating private keys and submitting certificate requests.
• Support for Extended Validation (EV).
  • An indicator (green bar) for EV certificates acts as an identifier in the Address Bar of the browser.

IRC

Opera supports the same preceding encryption standards for IRC.

Mail

Opera supports the preceding encryption standards for Mail. This includes:

• support for mail (IMAP/POP, SMTP) and mail encoded with MIME, HTML, SVG or RFC2822 (the current mail standard).

News

Opera supports NNTP, along with RSS and Atom feeds.

• A simple online newsreader with support for encrypted newsservers and newsservers with passwords is provided, which supports decoding of single article attachments, MIME or unencoded.

Unicode character set support in Opera

Opera can work with all the characters in the Unicode specification.

• All text communicated to Opera from the network is converted into Unicode.
• In order for Opera to render Unicode characters, the needed glyphs have to be available in the fonts on your system.
  • This might be a problem for older Windows systems supported by Opera, such as:
    • Windows 95®
    • Windows 98®
• For information on available fonts, see Unicode fonts for Windows computers.

Opera 9.5 implements the following writing system related functionality:

font-switching

needed in order to display characters that the current font does not include

line-breaking

needed in order to break scripts written without spaces, such as Chinese, Korean, and Japanese

Opera relies on the operating system to perform:

character shaping

contextual glyph selection, ligature forming, character stacking, combining character support and so forth.

Support for bi-directional text

Opera supports bi-directional text as described in Unicode, HTML, and CSS.

Legacy encoding support

Although Opera works with the Unicode character set and its character encodings of UTF-16 and UTF-8, most text on the Internet is encoded in legacy encodings.

Because many pages are mislabeled, Opera provides various options to find the encoding:

Auto-detect

In this mode, Opera will attempt to detect the encoding used by the Web page.

Writing script auto-detect

In this mode, the user can tell that this is a Japanese or Chinese Web page but that the encoding is unknown. Opera will then analyze the text in the Web page to determine which encoding is used.

Encoding override

In this mode, the user selects an encoding. This encoding will be used by Opera, regardless of what the Web page and transport protocol claims is the encoding for the Web page.

Raster Graphics

Opera fully supports:

• GIF89a
• JPEG
• BMP
• ICO
• WBMP
• PNG including alpha channel (degrees of transparency) and gamma support (device independent colors)
• APNG (Animated PNG images)

Scalable Vector Graphics (SVG)

• Complete table of SVG elements supported
• Complete table of SVG attributes supported
• Complete table of SVG CSS properties supported
• Complete table of SVG DOM interfaces supported

Events

There is support for listening to any event in the SVG module. Some events are not sent by core, for example: activate.

• SVG 1.1 doesn't specify a key-event set, and thus the attributes onkeyup, onkeydown and onkeypress do not register a corresponding event listener for those events.
• In Opera it is possible to install listeners for key-events with DOM, for example: element.addEventListener('keydown', keyhandler-function, false).
• If key-events are used it is vital to use evt.preventDefault() to prevent any key-event that should be handled only by the script from escaping upwards to the UI which may be listening for shortcut keys.

Integration

Opera supports the following SVG inclusion types:

• html:object element
• html:iframe element
• html:embed element
• html:img element
• in CSS:
  • background-image
  • list-style-image

Interoperability

Some content may fail to render if sent with the wrong MIME-type or if the namespace declarations are missing.

• The correct MIME-type for SVG is image/svg+xml.
• The namespaces to open are svg: http://www.w3.org/2000/svg and xlink: http://www.w3.org/1999/xlink.
• For CSS it should be noted that you must specify length values with units. For example:
  • font-size: 12; in CSS will mean the value is invalid, and thus it will be ignored.
  • This applies to all 'style' elements, 'style' attributes and external style sheets.
  • The CSS content property can also embed SVG.

Printing

SVG is output as a bitmap image to the printer.

• The output is not sent in vector format, thus the clarity of the image may be blurred.