User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b4) Gecko/20090423 Firefox/3.5b4 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b4) Gecko/20090423 Firefox/3.5b4 This is pretty similar to bug 490530 and 456382, but the later is closed and the former wants something different, so I'm filing a new bug. In 3.0 if you close the last tab it's replaced with a :blank window. This is very useful behavior, largely for the reasons mentioned in commetns 30 and 31 in 456382. But to re-iterate, I pretty much never want to close my browser completely, but I *do* often want to close the page I'm looking at. Either I'm done with it, or it it has some audio, or whatever. I think it's clear that closing the last tab shouldn't make the browser exit, but the option to close that tab is still nonetheless useful. This was the behavior in FF3.0 and I believe it to be the correct behavior. Reproducible: Always Steps to Reproduce: 1. Open browser 2. Go to webpage 3. Try to close tab Actual Results: Can't close tab Expected Results: Can close tab

I'm adding a "blocking-3.5" tag because I consider this a regression. Clearly if the developers don't agree then it can be changed.

Please never request blocking for unconfirmed bugs. That the close button is gone is by design -> bug 455990