So now you see my report. I have exactly the same bug as people in this thread describe. Only with FF 32 and Avast 2014.9.0.2021.

And it’s not the only program that “disabled” Avast breaks: https://forum.avast.com/index.php?topic=155905.0
You won’t call this thread outdated, will you? Of course, this is a different bug, but also happening with supposedly disabled Avast, when only uninstall resolves the issue.