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Firefox drops 100s of tabs upon restart

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Upon restart, Firefox has kept dropping (not loading) hundreds of tabs. 555 tabs, as also listed in my sessionstore, but after loading is finished, only about 330 is actually loaded of those. Previously, there have been similar issues with different sets, and loading the full set over, and over again, sometimes the full set or very close to the full set is loaded, indeed. But it is clear that there's a bug or at least a very inconsistent behaviour in the code somewhere. How can this be propely troubleshot and fixed? Happy to help. Thanks.

Upon restart, Firefox has kept dropping (not loading) hundreds of tabs. 555 tabs, as also listed in my sessionstore, but after loading is finished, only about 330 is actually loaded of those. Previously, there have been similar issues with different sets, and loading the full set over, and over again, sometimes the full set or very close to the full set is loaded, indeed. But it is clear that there's a bug or at least a very inconsistent behaviour in the code somewhere. How can this be propely troubleshot and fixed? Happy to help. Thanks.

Modified by BonanzaGroove

All Replies (7)

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jonzn4SUSE said

Bug filed. https://bugzilla.mozilla.org/show_bug.cgi?id=1802667

Not sure it is the same issue, but will be following it, thanks.

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Just did another attempt to load the previous session with the 554 tabs (3 windows in total, one main window with about 550 tabs and 2 further windows with 1 or 2 tabs each) and, apparently, all the 55x tabs have been loaded back. I am unsure how many - if any - tabs have still been lost, and this is only judging by the tab counters.

The steps I performed for the attempt were:

1. Open a brand new empty window 2. Close all the other open windows 3. Using the Tab Session Manager extension (that I am using to save the sessions), I again clicked 'Open' on the saved session with the 554 tabs. 4. Waited until all the tabs and windows were loaded one-by-one.

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Note that on Mac closing Firefox can be more complicated because you can close all open windows, but keep Firefox running with the menu bar visible or minimized in the Doc.

Make sure to use "Quit Firefox" with all windows still open, especially if you want to use "Restore Previous Session". Otherwise check "History -> Restore Previous Session" and "History -> Recently Closed Tabs/Windows".

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cor-el said

Note that on Mac closing Firefox can be more complicated because you can close all open windows, but keep Firefox running with the menu bar visible or minimized in the Doc. Make sure to use "Quit Firefox" with all windows still open, especially if you want to use "Restore Previous Session". Otherwise check "History -> Restore Previous Session" and "History -> Recently Closed Tabs/Windows".

Yes, that's what I did, indeed - yet, I am experiencing this issue. Thanks.

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You can check for problems with the sessionstore.jsonlz4 file in the Firefox profile folder that stores session data.

  • rename/remove sessionstore.jsonlz4 and sessionstore.js

You may also have to rename the sessionstore-backups folder.

When sessionstore.jsonlz4 is deleted you lose pinned-tabs and open tabs and you will have to recreate them, so if necessary make a note or bookmark them. sessionstore.jsonlz4 is only present in the Firefox profile folder when Firefox is closed.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page (Root directory).

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The sessionstore file is OK, as Firefox has finally been able to load all the tabs, after many attempts (as the same has happened many times recently). Not sure what problems I could check about it?