Mozilla Labs launches browser add-on for A / V recording
The add-on encodes video files in Theora and audio files in Vorbis and places them in an Ogg container. Future versions of the add-on will reportedly include live video streaming support, a "robust permissions mechanism" and support for WebM / VP8 video encoding as an alternative to Ogg / Theora.
Source: Mozilla The developers consider Rainbow to be at a pre-alpha stage of development and note that it currently only works with the nightly builds of Firefox for Mac OS X. Users testing the release are encouraged to provide feedback and report any bugs that they encounter. Support for Windows and Linux systems is said to be coming "in the near future". There are currently no plans to support earlier versions of Firefox.
Further information about Rainbow can be found in the announcement blog post and in the README file. Rainbow 0.1 is available to download from the Add-ons for Firefox page and an example is provided for developers. Source code for Rainbow is hosted on GitHub and is licensed under the Mozilla Public License.