Steps to Reproduce: 1. Set the menu font size of OS desktop to Tahoma 13pt or higher 2. Set browser.tabs.closeWindowWithLastTab to false 3. Open a webpage in one tab 4. Ctrl+W the tab to close it Actual Results: The height of Tab Bar changes. The content area seems to be shaked. The height of the tab changes when the menu font size of OS desktop is enlarged. This is easily reproduced in the third party theme (Walnut2 etc.) with a low tab. Walnut2 for Firefox https://addons.mozilla.org/en-US/firefox/addon/10610

There were some mistakes in my first report... This is reproduced on the trunk. This is not reproduced in the blank last tab function of Firefox 3.0.x. When the Message Box fontsize of OS desktop is Tahoma 13pt or more, this is reproduced. In short, 1. Large .tab-text -> The height of tab changes high 2. closing the last tab (Tab doesn't exist on Tab bar momentarily?) 3. The height of Tab bar changes This greatly limits height and the design of the third party theme.

> This greatly limits height and the design of the third party theme. The tab of the third party theme is limited.

AKIHIRO, can you verify that it has been fixed on 1.9.2?

Verified fixed with Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2b6pre) Gecko/20091221 Namoroka/3.6b6pre (.NET CLR 3.5.30729)