Don't know if this has already been posted but if like me you have upgraded to the newest version of Firefox only to find your extensions and themes don't work click here and try the "about config" tip. It's worked for me on two computers using "Reload Every" and "Google Toolbar for Firefox". All it does is fool the extension/theme into thinking the version of Firefox you have is actually an earlier build enabling them to work.
Thanks Irishman. 4-5 extensions stopped working when I moved from v1.0PR to v1.0, so I'm going to try the info in your link. A newer Googlebar extension (v0.9.0.30) has been released which works with v1.0 - click here. G