User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100905 Firefox/4.0b6pre Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100905 Firefox/4.0b6pre Sometimes tabs are "freezing" inside panorama (and winndows pinned button) and then i'm unable to close them (in example there is visible some webpage that i've closed - but X (close button) won't work - ctrl+w is impossible to use (because i can't open this "freezed" - ghost tabs)) Reproducible: Sometimes Steps to Reproduce: 1. Just open and close some tabs (ctrl+w and with mouse (X button)) 2. Check if there is some "freezed" - ghost tab, which is invisible in tabs bar and is impossible to close via panorama/win7 pinned icon Actual Results: There might apper some kind of ghost-tab (visible inside panorama and win7 pinned icon), but impossible to close or even open Expected Results: Tab that beed "marked" to close should close without leaving some ghost-tab inside panorama

I can confirm. Just a little correction, the tab IS VISIBLE in tab bar, but very small and it is not possible to click on it, but it is there and is interacting with other tabs, for example, when changing tab order by drag and drop. See the above attachment.

This sounds like a tabbed browser issue.