FWIW testing today, perhaps already yesterday, switched to version 8. Haven't read the thread, but IIUC there's an issue with backports regarding to version 8 for stable?! You could try to upgrade Iceweasel only from testing. OT: Won't capture this thread, so please don't reply to the following by this thread. I'll compile Firefox and try to install it parallel to Iceweasel. Btw. Iceweasel and Evolution don't work proper on my Xfce.