Advanced documentation

Opera is famous for its speed, security, flexibility, and standards support. These documents give you a look behind the user interface, and provide advice for changing files and using advanced settings.

Specifications

Opera prides itself in supporting all major web standards currently in use, including CSS 2.1, XHTML 1.1, HTML 4.01, HTML5, WML 2.0, ECMAScript, DOM 2 and SVG 1.1 tiny.

• Web specifications supported in Opera Presto
• Security specifications support in Opera Presto

Changing files and settings

• Browser JavaScript explained
• Command line options
• Opera.ini explained
• User CSS
• User JavaScript

Opera version history

Captures the history of Opera versions, technology, and major release features.

Changelogs

• The changelogs detail the changes made from previous desktop releases.
• The Opera Mobile/Opera Mini blog explains changes made from previous phone releases.

Administrator’s how-to

• Sysadmin’s handbook
• Opera’s kiosk mode
• Root certificates

Plug-ins and file formats

• Files used by Opera
• Plug-ins

Opera APIs

• Opera Extensions API guides
• Opera Link REST API