So i’ve been using firefox 3 beta, and now that firefox 3 rc 1 is out, i’m frustrated that my favourite add-on, namely imglikeopera, does not work with ff 3, and since the author has not updated it since December 2006(!), I decided to look for workaround to this, since it’s mainly an on/off switch extension, so it wouldn’t be too complex that it’s programmatically incompatible with ff 3.

Turns out it’s true, and with the workaround i can use imglikeopera again flawlessly with ff 3. It’s basically just editing the file install.rdf that comes with the xpi package. Here’s the link to the article :
How to install incompatible addons in Firefox 3