Web specifications support in Opera Presto 2.11

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Web specifications added since Opera Presto 2.10
Opera Presto web specification support pages


Opera Presto rendering engine

This document and its associated support tables apply specifically to the Opera Presto 2.11 rendering engine. It incorporates Opera Presto web specification support with the latest Core Milestone and integration point. Changes and additions occurring since Opera Presto 2.10 are identified with their specific Core Milestone integration points. Please see the following Core Milestone integration points added since Opera Presto 2.10 topic.

Opera desktop, device, and mobile products

Opera products use and depend upon various parts of the Opera Presto rendering engine and its web specification features. It is important to note that while the latest Opera Presto rendering engine has incorporated new web specification features, they may not have been added to the latest released versions of Opera products.

The Opera user agent string

Opera products will identify which Opera Presto version and core-integration-point they are using in their user agent string. Depending on your Opera product, the Opera user agent string is placed in the "About Opera" page, found by typing opera:about in the address bar, or by clicking "Help > About Opera" in the Menu.


Opera/9.80 (Windows NT 5.1; U; Edition Next; en) Presto/2.11.306 Version/12.xx

This example user agent string describes the Opera Presto 2.11 (Presto/2.11) rendering engine, incorporating core-integration-point 306 (.305).

A high-level overview of current web specifications support in Opera products is available on opera.com at: Web specifications support in Opera products: an overview.

Opera articles

For further reference, and where applicable, Opera web specification support table documents now contain hyperlinks to Opera technical articles written by leading subject matter experts. These are sourced from Opera's extensive developer website, dev.opera.com.

Web specifications added since Opera Presto 2.10

Important note

The following web specification items integrated into the Opera Presto rendering engine are identified with their (Presto/2.11.xxx) core-integration-point numbers. This identifies which web specifications are included with Opera product versions, as shown in their user agent strings. Please see the preceding description in The Opera user agent string topic, to associate Opera product versions with the Opera Presto core-integration-points they contain.

Implemented in core-integration-points 295 through 306

DOM support
Add support for DOM Events Level 3 - Key Events (Presto/2.11.295)
  • keydown, keypress, keyup events provide the properties defined by the specification below.
  • Legacy key attributes keyCode, which, and charCode support added/updated
  • keyCode values reported aligned with common internet practice
  • Navigation, function, and modifier keys no longer fire keypress events
  • On key repeat, keydown-keypress sequences are now reported
  • During IME composition, keydown and keyup will be delivered as required by the specification
  • A number of smaller compatibility issues have been addressed
  • See: Document Object Model (DOM) Level 3 Events Specification
Upgrade to full support for Range and Selection (Presto/2.11.305)

Implemented in core-integration-points 307 through 310

Add support for certain -webkit- prefixes (Presto/2.11.310)

Implemented in core-integration-points 311 through 319

Fullscreen API
Implement Draft 7 of Fullscreen API (Presto/2.11.311)
High Resolution Time
Add initial support for the high-resolution timer specification (Presto/2.11.319)

Implemented in core-integration-points 320 through 323

Add support for the slice() method over ArrayBuffers (Presto/2.11.322)

Implemented in core-integration-points 324 through 330

Add Window.matchMedia method and MediaQueryList interface to CSSOM View support (Presto/2.11.324)

Implemented in core-integration-points 331 through 337

W3C Text Encoding
UTF-16 byte order mark (BOM) now defaults to little-endian when no BOM is specified (Presto/2.11.334)
Remove handling of 5/6-byte UTF-8 sequences (Presto/2.11.334)
Update Unicode to 6.1.0 specification (Presto/2.11.335)
WebSocket API
Update WebSocket implementation to RFC 6455 (Presto/2.11.337)

Implemented in core-integration-points 338 through 345

Align XMLHttpRequest.setRequestHeader()'s allowed headers with specification: Content-Transfer-Encoding is now allowed, DNT (from Do-Not-Track) is now blocked (Presto/2.11.341)
Change handling of null and undefined in replaceState and pushState (Presto/2.11.341)
  • null passed as the 3rd argument of replaceState or pushState will now be ignored
  • undefined passed as the 3rd argument of replaceState or pushState will now be ignored
  • See: Web IDL
Google Gears
Remove support for Google Gears (Presto/2.11.344)

Implemented in core-integration-points 346 through 351

Page Visibility API
Add support for the Page Visibility API (Presto/2.11.348)
  • Add support for visible and hidden
  • Event is only sent when platform signals the window/tab visibility is changing
  • See: Page Visibility

Opera web specification support pages

HTML5 support
<canvas> element
New Elements/Attributes/APIs
Session History & Navigation
Legacy encodings support
MathML support
CSS Profile
Networking Protocols support
Offline Web Apps support
Offline Web Applications
SVG support
CSS Properties
DOM Interfaces
Text and internationalization support
Text & Internationalization
Web Open Font Format support
Web SQL Database support
Web SQL Database
Web Storage API support
Web Storage API
Web Workers API support
Web Workers API
WebSocket API support
WebSocket API
Widgets support
Access Request Policy (W3C)
Interface (W3C)
Packaging & Config. (W3C)
URIs (W3C)
Format specification (Opera)
XML Digital Signatures
XML support


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