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Hidden tab won't close, constantly loading.

  • 4 replies
  • 6 have this problem
  • Last reply by cor-el

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There's a tab on my Firefox that doesn't show on the window. It seems to be a tab that was previously open, that I thought I'd closed. While it doesn't show on the window, the tab preview when I mouse over it in the windows taskbar shows that the tab is still open. When I click the x in the preview, the tab won't close. Also on mousing over the tab, it shows that the page is blank, but it seems as though it is loading something. It may or may not be causing my computer to run slower than usual, but I can't be sure. Either way, it's annoying and the only way I can get rid of it is by restarting my browser, but even then after using the browser for a while another tab like that shows up and I run the same problem. How do I close a tab like this?

Extra notes: The tab is not open from the start. It is not a homepage, as my homepage is set to about:blank, and opening a homepage upon starting my browser is disabled. The tab is not visible on the Firefox window. It is only visible on the windows preview when mousing over the Firefox application in the windows taskbar.

All Replies (4)

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The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information such as bookmarks and history. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

Thank you.

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The problem has existed since I first downloaded Firefox; resetting to factory defauly isn't going to remedy the problem.

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In order to better assist you with your issue please provide us with a screenshot. If you need help to create a screenshot, please see How do I create a screenshot of my problem?

Once you've done this, attach the saved screenshot file to your forum post by clicking the Browse... button below the Post your reply box. This will help us to visualize the problem.

Thank you!

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You can check for problems with the sessionstore.js and sessionstore.bak files in the Firefox profile folder that store session data.

Delete the sessionstore.js file and possible sessionstore-##.js files with a number and sessionstore.bak in the Firefox profile folder.

Deleting sessionstore.js will cause App Tabs and Tab Groups and open and closed (undo) tabs to get lost and you will have to recreate them (make a note or bookmark them if possible).

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window or otherwise make changes.

You can check for problems with preferences and rename or delete the prefs.js file and possible numbered prefs-##.js files and a possible user.js file to reset all prefs to the default value.