Firefox 5 extension compatibility check

The old preference for disabling compatibility checks (extensions.checkCompatibility) is now gone. The new one marks the version you chose to do this at:

To re-enable your broken (but likely still working) add-ons in Firefox 5.0, add the extensions.checkCompatibility.5.0 preference in about:config:

1. Type about:config into the firefox URL bar.

2. Click I’ll be careful, I promise

3. Right-click and select New > Boolean

4. Enter extensions.checkCompatibility.5.0

5. Select false

6. Restart Firefox