User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.8.1) Gecko/20061010 Firefox/2.0 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.8.1) Gecko/20061010 Firefox/2.0 1. Ensure that there is a tab to the right of the tab you have open **right now**. 2. Ensure that "When I open a link in a new tab, switch to it immediately" (in Tools-->Options-->Tabs) is disabled. 3. Middle-click a link on the current page (such as 'View Bug Activity', above) while holding Shift, thereby opening the link in a new tab -- with focus. 4. Close the current tab (the current tab is the tab opened in step 3). Actual: The tab-to-the-right is focussed. Expected: The tab containing this Bugzilla page is focussed. The basis for this expected result is that Shift+middle-clicking a link is an intermediate step. See <http://wiki.mozilla.org/Link_Targeting#Moving_Focus_after_Closing_Tabs>. Reproducible: Always

Just to add: In step 1, make sure that the tab-to-the-right is *not* blank.

This is strange -- for me, the expected result occasionally *does* happen, but usually not.

Does this still happen? Have you tried it in safe-mode?

WFM Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.3) Gecko/20090824 Firefox/3.5.3