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A 2nd copy of firefox opens with a black screen when opening Firefox

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  • 6 have this problem
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  • Last reply by shoinka

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After Firefox loads with the home pages, a second copy of Firefox also opens with one black screen. The black screen has the same url as the 1st tab in the 1st copy of Firefox, with one addition as follows: 1st copy, 1st tab url: www.newsmax.com 2nd copy (no tabs) url: www.newsmax.com/mainpop.htm

I'm using Windows XP, sp3, and Firefox version 10.0.1. It does the same on another desktop with Windows 7, same Firefox version(10.0.1).

After Firefox loads with the home pages, a second copy of Firefox also opens with one black screen. The black screen has the same url as the 1st tab in the 1st copy of Firefox, with one addition as follows: 1st copy, 1st tab url: www.newsmax.com 2nd copy (no tabs) url: www.newsmax.com/mainpop.htm I'm using Windows XP, sp3, and Firefox version 10.0.1. It does the same on another desktop with Windows 7, same Firefox version(10.0.1).

All Replies (2)

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It is possible that there is a problem with the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.

Delete the sessionstore.js [2] file and possible sessionstore-##.js [3] 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, so you will have to create them again (make a note or bookmark them).

See also:


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

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Thank you for the reply. Unfortunately I couldn't get it to work. I did delete the sessionstore files, but that didn't help. I opened firefox in safe mode, and really didn't know how to check to see if the extensions or hardware acceleration were the problem.

I did stumble on something that worked, but really isn't a permanent solution. I simply opened a second copy of firefox, and it came up with all my default tabs, without the extra, black window. (I had 2 firefox sessions opened at the same time. The 2nd one was ok.

Maybe that will give you a clue. Thanks