But, oh no! My favorite addon is not (yet) compatible with 3.5! What ever shall I do? Woe! Woe is me!
Or not. Just because Firefox doesn't think that an addon is compatible, doesn't make it so. Some, I daresay many, of the "incompatibles" will work just fine in the new version, they just haven't been added to the list of compatible addons yet.
In my case, the "Can't-Live-Without-It" addon is Link Alert. An extremely handy addon that adds a little icon next to the mouse pointer whenever it passes over a link. the icon indicates what kind of link it is (mailto:, new window, archive file, etc.) It's gotten so that I feel quite naked without it.
But it's "not compatible" with 3.5? Ah, but it is! I must merely force it down Firefox's throat! Here's how (this works on all platforms):
Open up a new tab in Firefox 3.5.
In the address bar, type about:config and press enter. If this is the first time you've used about:config, then you'll get a waring page:
Click the "I'll be careful, I promise!" button to continue.
Now, in the about:config page, right-click anywhere and select New>boolean. In the "New Boolean Value" box that appears, copy this text: extensions.checkCompatibility then click OK.
In the "Enter Boolean Value" box that pops up next, click False and then ok.
Now restart Firefox and your incompatible addons will be enabled!
If Firefox acts weird, or won't start at all after doing this, read this article about starting Firefox in safe mode.
Edited by Amazing Andrew, 01 July 2009 - 12:54 PM.