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How can I get Firefox 91 to ask if i want it to restore previous session?

Freak3150
Freak3150
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I've always had Firefox ask if I want to restore the previous session, so that I can get rid of unwanted tabs without having to click through them all one by one. It used to start to that page, but several updates ago it stopped.

I checked and I have the "browser.sessionstore.max_resumed_crashes" in the about:config page set to 0 which according to everything I can find should bring up the page that I'm looking for when I start after closing it out with the Task Manager, but it isn't working. It just restores everything automatically, without taking me to the page I can check off which tabs and windows I want restored.

I'm using Firefox 91.0 (64 bit) and Windows 10.

Thanks for any help.

I've always had Firefox ask if I want to restore the previous session, so that I can get rid of unwanted tabs without having to click through them all one by one. It used to start to that page, but several updates ago it stopped. I checked and I have the "browser.sessionstore.max_resumed_crashes" in the about:config page set to 0 which according to everything I can find should bring up the page that I'm looking for when I start after closing it out with the Task Manager, but it isn't working. It just restores everything automatically, without taking me to the page I can check off which tabs and windows I want restored. I'm using Firefox 91.0 (64 bit) and Windows 10. Thanks for any help.

All Replies (3)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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The max_resumed_crashes preference is only consulted if Firefox believes that it last closed by crashing. It is not used if Firefox exited normally.

Unfortunately, I'm not aware of any other way to get to that screen.

If you do not want Firefox to restore your previous session automatically, make sure "Restore previous session" is NOT checked on the Settings page.

Freak3150
Freak3150 Question owner
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I don't exit it normally, I use the task manager to close it, which (to my understanding) is supposed to appear to Firefox as a crash. I've had this happen before after updates, and setting this to 0 always fixed the problem until recently. (It's actually been a few months, but I've been trying to find some info on how to fix it, and finally gave up and created the account here)

Does Firefox no longer look at a task manager close as a crash? Something has obviously changed. Maybe it's on the Windows side of things? Like the TM doesn't close it in a way that gets interpreted like a crash anymore?

If I uncheck the "restore previous session" I'll lose all the windows/tabs. I just want to be able to pick which ones I want to restore.

Thanks for the info though. Hopefully I can find a workaround.

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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Here's one other thing to check:

Sometimes users get a user.js file with an entry that instructs Firefox to resume the last session once but the way a user.js file works, that instruction is re-read at every startup. This article has info on how to check whether you have a user.js file (find it in the table of contents):

How to fix preferences that won't save