This actually does happen after awhile and is generally related to using the same profile in Firefox for months/years and getting overly cluttered or just having a lot of extensions (men) going in and out of there (Kat's house) and *** things up over time, to put it simply. I generally to wipe and replace my profile every few months or at the beginning of a big update since old settings tend to conflict when drastic changes are made. Not much different from Windows in general, being why some format their computers like once every 6 months and reinstall. In that way those profile backup programs/extensions can be a blessing and a curse if they're just a long continuation of whatever problem you originally had.
Here's a fairly simple fix for testing just where your problem lies, guys. Assuming you aren't using a portable version like what Anye posted about a few days ago for use in flash drives this should work. Specific intructions can be found here, but I'll give a basic rundown of what to do as well:
http://support.mozilla.com/en-US/kb/Managing+profiles
Firstly, in the menu bar, click
Help > Check for Updates just to make sure you're starting out on the right foot.
After, (in Windows) close Firefox, go to
Start > Run then enter "
firefox.exe -p" or "
firefox.exe -profilemanager." This will bring up, you guessed it, Firefox's profile manager wherein you can create a new profile that's completely blank (and clean) and see if your problem persists. If so then you know it's either a default setting in Firefox which is likely to have a fix courtesy of Google, or a problem with your install in general that may be solved by Uninstalling Firefox, restarting then reinstalling.
If they problem is gone with your new profile, then you at least know something in your old profile *** things up! You can either try to hunt down the perpetrator or start clean, in which case I have a few tips on how to get your profile back to normalcy fairly quickly since I've had to do it a few times. lol
@Azul: What distro are you using? I like the UI a lot. Get some damn bookmarks, though! Bookmark bar is so barren. :<
*checks for updates to
the Bible*
No hitting, Kat. 83