Today's update of Firefox to the 29 version makes browsing very slow.
For example Firefox incredibly lagging when I am zooming or moving on google maps.
Does anyone the same problem? How can I speed it up?
My OS: Ubuntu 12.04, x64
You could try to reset Firefox to factory defaults, this is actually something Firefox proposes to do if it detects that the start-up takes too long. Beware, however, this procedure will delete all your installed add-ons and your search engine settings.
To do a factory reset, follow the instruction on this page.
Another thing you could check is whether hardware graphics acceleration is set up correctly. The answer to this question describes how to do that.