(Note: this is filed as part of the “Paper Cut” bugs — we assume that there may be multiple existing bugs on this. Please make them block this bug, and we will de-dupe if they are indeed exactly the same. Thanks!) To reproduce: 1. Open a lot of tabs in firefox so that your tabs become fairly small 2. Start closing tabs 3. Notice that the tabs resize while you are closing so that you have to move your mouse to close the next tab. Recommendation: Do not resize tabs wile a user is closing multiple tabs until the user mouses away from the tab bar. Google Chrome does this. Here is an excellent write-up on the subject: http://www.theinvisibl.com/news/2009/12/08/a-piece-with-a-lot-of-screenshots-about-the-close-tab-behaviour-in-google-chrome/