How to force extensions to be enabled in Firefox beta

Many Firefox add-ons are not yet updated to support Firefox3, even though they probably work fine anyway. You could try bypassing the extension compatibility check by following this guide. This is not recommended as it may break your installation of Firefox, but it worked fine for me.

1. Start at Firefox’s address bar and type this in:
   about:config
2. Right click anywhere in the list and select New then Boolean
3. Enter extensions.checkCompatibility when it prompts you for a preference name.
4. Select False for the boolean value.

You have just told Firefox not to check extension compatibility. Now cross your fingers, restart Firefox, and hope for the best!