FireBug 2.0 Deactived ??
I have always been able to use Firebug but recently I went to right click a page I was working on and selected "Inspect Element with Firebug" and absolutely nothing happened. I then clicked "Inspect Element (Q)" and the built in one worked..
I then checked the "Add-ons" listing and firebug 2.0 has "Disable" and "Remove" which means that it is ENABLED and should be working. However when I mouseover the Firebug BUG icon in the top right portion of the page it says "Firebug 2.0 Deactivated".
I REMOVED firebug and re-installed it and same thing. I then went into safemode but then you cannot enable it manually so that didn't work.
I'm using the newest (as of now) Firefox 31.0
Did you try to right-click (or possibly left-click) that toolbar button as this means that Firebug is installed, but currently not activated as is usually recommended if you do not need Firebug for the current session?
Firefox 30 is the latest Release version. Firefox 31 is a Beta development version.
It's "deactivated" on every page and every website I try. I right clicked and clicked "Enable all panels" and nothing happens..
Firebug usually supports all Firefox developer versions, so I would expect it at least to work with a beta.
You can try to remove all lines in the prefs.js file that refer to firebug as this might be easier than using the about:config page. You need to do this while Firefox is closed.
You can also try to uninstall and reinstall Firebug to reinitialize the extension.