This happens on both Fedora 20 and Ubuntu 14.04 with XFCE DE. When I click on any link (from external program), a new firefox window is opened with start page. That's all. I've already checked for launch command - "firefox %u". I have no idea what's the problem and what to do. Help, please.

I found out that only way - downgrade firefox. It lost his convenient menu, but problem is solved now. I'll be waiting hopefully for new version of firefox. Or, maybe, there is any other solution?