User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:2.0b9) Gecko/20110117 Firefox/4.0b9 Build Identifier: Mozilla/5.0 (X11; Linux x86_64; rv:2.0b9) Gecko/20110117 Firefox/4.0b9 I think this is a regression after upgrade to 4.0b9 but I'm not absolutely sure. When entering text in the location bar, it offers links as usual. Additionally, it offers to switch to open tabs. I know that feature, I like it, and I've seen it working. However, several times now I wondered if there was a firefox window I had forgotten about because I was offered to switch to an open tab (containing the linked page). So although I can't say how to reproduce it, I can say that this happened a few times now. I couldn't find it in bugzilla so I'm reporting it here. With beta9, FF4 really is fun to use and much more stable than the other betas! Reproducible: Sometimes I'm using the build from an inofficial ("Spot's") Fedora repository.

Erm, maybe it's not clear from what I wrote: The actual problem is that a tab switch is suggested although no such open tab exists. It happens with links in my history.

Do you have bartab installed, by chance?

BarTab isn't installed. Sorry for the dupe, I'll subscribe there.