How To Bypass Firefox 4.0 Beta S Incompatible Add On Error And Install Extensions Anyway

Here’s the error message we’re talking about:

Side note: want to test the new beta out for yourself? Head over to the Firefox Beta site, though it’s really in beta, and has a lot of changes, so you’ll want to think carefully before you do so.

Open up the about:config page, and then right-click anywhere and choose New –> Boolean.

You’ll get a popup menu, at which point you’ll want to use one of the two values as the preference name, depending on the version you’re using:

4.0 Release: extensions.checkCompatibility.4.0

Then set the value to false.

At this point your extensions should install just fine…

Important Note: At the moment of the writing of this article, Greasemonkey is really actually incompatible with Firefox 4.0 beta, and continually opens up the homepage with a never-ending list of tabs. The same goes for quite a few extensions that we tested, though some of them worked fine. We’re pretty sure they’ll be updated very soon.