Web specifications support in Opera Presto 2.12

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Web specifications added since Opera Presto 2.11
Opera Presto web specification support pages


Opera Presto rendering engine

This document and its associated support tables apply specifically to the Opera Presto 2.12 rendering engine. It incorporates Opera Presto web specification support with the latest Core Milestone and integration point. Changes and additions occurring since Opera Presto 2.11 are identified with their specific Core Milestone integration points. Please see the following Core Milestone integration points added since Opera Presto 2.11 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/2.12.355 Version/12.xx

This example user agent string describes the Opera Presto 2.12 (Presto/2.12) rendering engine, incorporating up to core-integration-point 355 (.355).

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 2.11

Important note

The following web specification items integrated into the Opera Presto rendering engine are identified with their (Presto/2.12.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 355 through 359

High Resolution Time
Disable performance.now() (Presto/2.12.355)
Web Workers
Update SharedWorker connect events to use .source (Presto/2.12.355)
  • Latest specification allows 'incoming' port for a SharedWorker to be communicated via source as well as ports[0]
  • See: Web Workers
Remove input.selectedOption (Presto/2.12.355)

Implemented in core-integration-points 360 through 364

Add support for the <track> element and WebVTT (Presto/2.12.361)
User Agent
Add support for Device-Stock-UA header (Presto/2.12.362)
CSS TV Profile
Change default state of preload to auto (Presto/2.12.362)
Update CSS3 - Gradients support (Presto/2.12.364)

Implemented in core-integration-points 365 through 374

Add support for the selectionDirection property on input and textArea elements (Presto/2.12.370)
Add support for the reversed attribute on ordered lists (Presto/2.12.372)
Add support for nested @media rules (Presto/2.12.374)

Implemented in core-integration-points 375 through 378

Add support for the SPDY protocol (Presto/2.12.376)

Implemented in core-integration-points 379 through 395

Upgrade libwebp to version 0.2.0: lossless WebP images are now supported (Presto/2.12.382)
Add partial support for resize property (Presto/2.12.389)
Re-add -o- prefix and legacy syntax for linear-gradient, transition, transform (Presto/2.12.392)
Add support for new DOM4 Node methods (Presto/2.12.392)
Make title parameter of createHTMLDocument optional as per spec (Presto/2.12.394)
Add support for WebGL float texture extensions (Presto/2.12.394)
Elliptic Curve Cryptography
Add support for Elliptic Curve Cryptography (Presto/2.12.395)

Implemented in core-integration-points 396 through 406

Service Discovery API
Add support for a subset of the Service Discovery API (disabled by default) (Presto/2.12.397)
Add support for @supports (Presto/2.12.401)
Add support for Flexbox (Presto/2.12.403)
Add support for <track> subtitles/captions (Presto/2.12.402)

Implemented in core-integration-points 407 through 423

Add support for link.relList + a.relList (Presto/2.12.407)
Add DOM4 support for DOMTokenList.add() + remove() (Presto/2.12.407)
Spatial navigation
Spatial navigation, which allows you to move focus to any link or form input using shift + arrow keys, no longer highlights links that are invisible due to z-index stacking (Presto/2.12.417)

Opera web specification support pages

ECMAScript support
Graphics support
HTML and XHTML support
DOCTYPE Switches
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
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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