The Firebug team released Firebug 2.0.19. This is a maintenance release ensuring compatibility with latest Firefox releases.
The beta channel on AMO is also updated.
Firebug 2.0.19 is compatible with Firefox 30 – 54
Firebug 2.0.19 fixes issue 8077.
You might also want to read about Unifying Firebug & Firefox DevTools.
Please post feedback in the newsgroup, thanks.
Jan ‘Honza’ Odvarko