Getting started with Opera (.oex) Extensions

This documentation relates to Opera's now deprecated .oex Extension API framework for Opera versions <= 12.15 and also provided by our OEX2NEX shim library.

For the latest Opera Extensions API documentation for Opera versions > 12.15 please consult the latest Opera Extensions API documentation online.

UI guidelines and distribution

API reference

You can build Opera extensions using the Opera Extensions APIs and open web standards like JavaScript and HTML. This makes Opera extensions easy to create, quick to debug, and fast to install.

Basics and UI elements:

Browser functions:

Finishing up:

Extension tutorials

Templates and code samples