In my case (am seeing it on windows), it started to happen since I have applied Windows Update (which may or may not be involved: KB982110, KB2272691, KB947821).

I could get it working after I disabled adblock plus and google toolbar.

I have these addons installed: all-in-one sidebar, cooliris, echofon, firebug, firefinder for firebug, greasemonkey, java console, libron, memory fox, personas, tab mix plus, tombloo, web developer. I have tried them one-by-one and verified they are not the blocker (unless add-on combination and/or installation orders matter).

It might be dependent on plugins, but no further idea. Google toolbar caused the issue either with or without Google Update.

Count me in as having the Google toolbar errors as well.

I also hang when I'm updating a add-on. I get this message:

A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.

Script: file:///C:/Program%20Files%20(x86)/Mozilla%20Firefox/components/nsExtensionManager.js:623

I have to kill FF sometimes more than once to get it to open up without stalling. Please advise. Windows 7 x64 Firefox 3.6.8

I saw on another thread that it is the Persona's add on that's causing the problem. Disable it and all should be fine again

If you have Personas installed, please read this article and its review:

https://addons.mozilla.org/en-US/firefox/addon/10900/

Is there a way to disable an add-on without access to the add-on menu?

I have successfully disabled the addons by going this route;

http://kb.mozillazine.org/Safe_Mode

Well this sucks.

Apparently my about:addons page crashes whenever I have one of THREE addons enabled: Skipscreen beta, Tor button alpha (these two are understandable they're both not stable and Skipscreen isn't even supposed to be Fx 4 compatible) and strangely enough, Testpilot. Now I find it hard to believe these three very different addons all have the same bug but whenever I enable any one of these three about:addons will crash firefox WITHOUT FAIL, either on start-up or when refreshing the page, and I can't seem to reproduce this without these addons enabled.

Whatever this is, hope it's fixed soon.

Firefox version: Mozilla/5.0 (X11; Linux x86_64; rv:2.0) Gecko/20100101 Firefox/4.0 ID:20110322135802

about:support: http://pastebin.com/9X0N5sQK

Edit: I just tried a clean profile with just torbutton alpha, Skipscreen Beta and Testpilot installed and that ran perfectly, so it would seem there may be another add-on in the mix, or it might be something completely different. I did find it suspicious that all three offending add-ons were directly below one another.

But a fix it is not.

hello i found problem for crash when i open addons menu, crashed from extentions:

- personas plus - personal menu - trackmenot - Tweak Network

but does mozilla firefox has an app for check compatible extentions? please to check it all extentions because i'm tired this problem...

to remove exntension: go to safe-mode and addons, remove extentions.. byebye

I found disabling CGPS which is a comcast Constant Guard program stopped Firefox from crashing. Whew.