Whenever a new version of Firefox comes out there's always some grumblings about it deciding that certain extensions are now incompatible. It seems especially needless with so minor a version change as 1.5 to 1.5.0.1.


The fix is not new but not widely known:

In the address bar type about:config. Use the Filter field to find app.extensions.version (if it's not present, create it by right-clicking and choosing New > String). Double-click on it and in the pop-up box enter 1.5 (or the previous version of your choice--if you're creating a new value the box will pop up automatically). Restart Firefox and when it's started go to Tools > Extensions. Find the "incompatible" extensions in the list (they'll be greyed out), right-click on them, and click Enable. Restart Firefox and you're done.

And as always, the above tip is at-your-own-risk and YMMV. For more technical information check out Extension Versioning at Mozilla.org.