Recent answers to Firefox will not close tabs (with "x" or keyboard shortcut)https://support.mozilla.org/en-US/questions/7460172011-09-25T18:56:07-07:00Try disabling the AddThis extension. It worked for me, tabs closed immediately.
2011-09-25T18:56:07-07:00dacwhohttps://support.mozilla.org/en-US/questions/746017#answer-251405<p>Try disabling the AddThis extension. It worked for me, tabs closed immediately.
</p>Start here: Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox2010-08-04T09:12:37-07:00AliceWymanhttps://support.mozilla.org/en-US/questions/746017#answer-1<p>Start here: <a href="/en-US/kb/troubleshoot-extensions-themes-to-fix-problems" rel="nofollow">Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems</a>
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