Firebug and Firefox 3 Beta 5

After installing Firefox 3 beta 5 I had a lot of trouble with the Google Toolbar. After disabling the check for Extensions, Firefox didn't start anymore.
Now I fixed the problem by removing Google Toolbar, but an Add-on I really need is Firebug. For web development, there is no better tool for debugging your page.
Unfortunately the current version of Firebug doesn't support Firefox 3. But instead of the Google Toolbar it works after disabling compatibility check.
Or better it works pretty fine on my Mac and on a Windows XP machine, but it fails on my Ubuntu Hardy Heron machine, where Firefox 3 is the default browser.

Firebug on Firefox 3 RC1 (Mac OS X)

But thanks to Ubuntu team there is a great solution. You can install Firebug as a package from the Ubuntu repositories. This version of Firebug works great in Firefox 3 beta 5 in Ubuntu.