User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; cs; rv:1.9.2.10) Gecko/20100914 Firefox/3.6.10 ( .NET CLR 3.5.30729) Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; cs; rv:1.9.2.10) Gecko/20100914 Firefox/3.6.10 ( .NET CLR 3.5.30729) If there is only one tab open then the close button on the tab disappears. This feature should be disabled if browser.tabs.closeWindowWithLastTab is false. The close button is quite important because if there is a Flash or other element stealing focus from Firefox then there is no easy way to close this tab with single click or keyboard shortcut. Reproducible: Always Steps to Reproduce: 1. Set browser.tabs.closeWindowWithLastTab to false. 2. Open window with a single tab. Actual Results: No close button on the tab. Expected Results: Close button on the tab.

Maybe dup of Bug 501714