So I had this problem when I upgraded to 6, and I was able to "repopulate" them by going to Options > Tabs. The thing was, I didn't toggle any flags. When I exited the Options menu, the "x" option in tabs magically appeared. Seems to be a small bug.

That got it. Tks.

BTW, the X did show one time b4 I originally posted this issue. But then it disappeared and didn't reappear. This time apparently it stays put :)

Tks again.

The Option Tabs trick did not work for me. The X's do reappear if I open 3 or more tabs and then close one with 'right click close'. However, if I then close all but one tab, the X's disappear and I have to repeat the open 3, right click close to get them back.

One thing I did do but didn't mention: I changed a selection--> I put a check in the "When I open a link in a new tab , go to it immediately".

Closed the options dialogue box, closed FF and restarted FF.

I always get the "x" now.

Changing the Tab options and restarting FF doesn't work for me. This is nothing but a bug that simply needs fixing.

Here's a workaround that brings back the "X" (for now, until we see a real fix):

1. Make sure you have at least 3 tabs open (no need to load a page, those extra tabs can be empty)

2. Once you've got 3 or more tabs open... right-click on any tab other than the first one and select "Close Tab"

Yes, the "X" will now appear on the other tabs, and any new tabs you open. However, it's only good: (a) if you KEEP OPEN 2 or more tabs and (b) for that browser session. Once you close all but one tab, or close FF and open it again... you no longer have the "X".

Silly bug!

Thanks! That does work for me.

Still no X if only one tab is open. Opera and IE9 have X even if only one tab is open. In IE9, clicking on the X with only one tab will close IE9 altogether while Opera closes that tab and returns to Speed Dial tab. Personally, I like Opera's style best. FF6 does not allow the single tab to be closed, so the closest thing to approximate Opera is to open a tab to your home page (or a blank page), right click and "Pin as App Tab". This minimizes the tab width and if you only pin one tab, you can close all the rest and return to the page you've pinned. But you have to do this each time you open FF6, so it's still not very user friendly!

This is a bug, since version 6.

I randomly disappears, and then randomly comes back.

I had the same problem. All I did was close the browser completely and restart it and all my tab x's were restored. I even restored the previous browsing session and all the x's were there this time.

Another bug.

Great. More bugs foisted upon the users because Mozilla couldn't take its time to get them ironed out in beta before making it a scheduled update.

Mozilla should have ironed out the problems with 4.x before moving to a new, buggy 5.x then a new, buggy 6.x