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Dozens of new tabs keep opening in Firefox 40.0.2

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There are dozens of new Tabs open on the Tabs bar. What is causing this?

There are dozens of new Tabs open on the Tabs bar. What is causing this?

All Replies (11)

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These are not tabs restored from a previous session that somehow got corrupted and blanked, these are new tabs?

One possibility is that you downloaded something and when Firefox asked what application should open the download, you specified that Firefox should handle it. That can create an infinite loop. If you ever saved that setting in the past, it can come back to haunt you unexpectedly. This article addresses that problem: Firefox repeatedly opens empty tabs or windows after you click on a link.

Another possibility is that the site or an add-on or another program is trying to flood you with popups but they are turning into tabs. Usually in that case the tabs would have some content pointing to the intended purpose of the tabs. If they are just blank new tabs, that doesn't really help in identifying the culprit. As a test, you could restart Firefox in its Safe Mode. That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement? If not, we can rule out extensions as a source of the problem.

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You can get tabs opening endlessly if you select the Firefox program to handle a file when you get an "Open with" dialog.


If the tabs open when you start Firefox then check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. 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).

You can use this button to go to the current Firefox profile folder:

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What is in these unwanted tabs?

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jscher2000 said

These are not tabs restored from a previous session that somehow got corrupted and blanked, these are new tabs? One possibility is that you downloaded something and when Firefox asked what application should open the download, you specified that Firefox should handle it. That can create an infinite loop. If you ever saved that setting in the past, it can come back to haunt you unexpectedly. This article addresses that problem: Firefox repeatedly opens empty tabs or windows after you click on a link. Another possibility is that the site or an add-on or another program is trying to flood you with popups but they are turning into tabs. Usually in that case the tabs would have some content pointing to the intended purpose of the tabs. If they are just blank new tabs, that doesn't really help in identifying the culprit. As a test, you could restart Firefox in its Safe Mode. That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode. If Firefox is not running: Hold down the Shift key when starting Firefox. If Firefox is running: You can restart Firefox in Safe Mode using either:
  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled
and OK the restart. Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh). Any improvement? If not, we can rule out extensions as a source of the problem.
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Thank you for your quick and thorough reply. I just refreshed Firefox to halt the endless loop of New empty Tabs, and I am resetting only those tabs that I actually want. If this is a fault of Firefox 40, hopefully the engineers will fix this issue. Thank you again for your reply, and especially for you help. Sincerely----- Doc

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cor-el said

You can get tabs opening endlessly if you select the Firefox program to handle a file when you get an "Open with" dialog.

If the tabs open when you start Firefox then check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. 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).

You can use this button to go to the current Firefox profile folder:

more options

cor-el said

You can get tabs opening endlessly if you select the Firefox program to handle a file when you get an "Open with" dialog.

If the tabs open when you start Firefox then check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. 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).

You can use this button to go to the current Firefox profile folder:

more options

FredMcD said

What is in these unwanted tabs?
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Thank you for your reply.

The New Tabs were all empty.

I just refreshed Firefox to halt the endless loop of New empty Tabs, and I am resetting only those tabs that I actually want. If this is a fault of Firefox 40, hopefully the engineers will fix this issue. Thank you again for your reply. Sincerely----- Doc

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Doc10 said

cor-el said
You can get tabs opening endlessly if you select the Firefox program to handle a file when you get an "Open with" dialog.

If the tabs open when you start Firefox then check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. 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).

You can use this button to go to the current Firefox profile folder:

more options

Thank you for your quick and thorough reply. I just refreshed Firefox to halt the endless loop of New empty Tabs, and I am resetting only those tabs that I actually want. If this is a fault of Firefox 40, hopefully the engineers will fix this issue. Thank you again for your reply, and especially for you help. Sincerely----- Doc