Firefox 2.0 disables all extensions that are not mentioned as compatible with 2.0 by their authors.
Most however can be made to work with firefox 2.0 using am a extension called
Nightly Tester Tools to make the extensions compatible
Download and install the extension.
Restart firefox afterwards and click on tools then add-ons.
Click `Make all compatible` and restart firefox again.
All extensions
should now be compatible with firefox 2.0. If there are problems with incompatibilities, deactivate all extensions again and activate one by one to see which one is causing the problem. Then wait for that author to write an update.
(info from gHacks)
