Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Using a stock Firefox install of 3.6.6 install, there's no close button if there is only one tab open. Here's the current behavior when I middle-click on that tab:

  • nothing happens

Here's the behavior I want when I middle-click on that tab:

  • web page disappears
  • same tab remains, but it's now blank

How can I make Firefox behave this way? I've had it before, but I don't know if it was an addon (likely TabMix Plus) or a tweak I made to the stock browser?

I really want this without installing addons, but I accept that an addon may be required.

share|improve this question
up vote 1 down vote accepted

In about:config, set


to false.

Edit: This works on my iMac; doesn't on my macbook. No idea what's different, YMMV.

share|improve this answer
This does not put a close button on the tab. It does allow me to close the tab w/ a middle click (which flashes a close button on the tab, for an instant, as it's closing). When the tab closes, a blank tab immediately replaces it. The browser does not close. That'll do until I can get TabMixPlus. – lance Jul 21 '10 at 21:23
In Preferences | Tabs, unticking "Always show the tab bar" will allow that only remaining tab to actually go away. Close-buttons are controlled by another about:config variable, "browser.tabs.closeButtons". This page in Mozilla's Knowlegebase describes the possible values and their behaviors: . – JRobert Jul 21 '10 at 22:20

Tab mix plus does this, but you have to do a little tweak to it go to Tab Mix Plus Options -> Events -> Tab Closing -> Closing Last tab, and check "Do not close window when closing last tab".

EDIT: There is no way to do this without tab mix plus.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.