This document briefly describes Opera's Plug-in Application Programming Interface (API).
If you need information about installing and configuring plug-ins for Opera, see the Opera and plug-ins page.
Opera is currently implementing the Netscape4 plug-in API. The Netscape4 plug-in API is used in the Netscape4 Communicator/Navigator products. It is also partly supported by Mozilla and the Netscape6 browsers.
The plug-in API function signatures are found in the include files which come with the plug-in Software Development Kit (SDK).
Unless specified in the plug-in guide, the plug-in authors should not write plug-ins which in some way depend on the invocation order. For instance, a plug-in should not depend on how often or when the browser calls NPP_SetWindow.
LiveConnect is supported.