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After some background activity I lost 4 of the 7 windows
After some background activity Firefox Version 64.0 (64-bit) running on Windows 10 Home (x64) Version 1803 (build 17134.472) seemed to restart and came back with 3 of the 7 windows most of which were minimized. The other four had disappeared without trace.
Does anyone have an idea how this happened? Could it be prevented, can it be fixed and more importantly can those windows be retrieved?
Any help would be greatly appreciated.
All Replies (3)
What is "after some background activity" is that were talking about? Your making vague problem request and no one will be able to re-create the problem to see what is going on.
Firefox should normally remember/restore all open windows.
Did you check for closed windows (History -> Recently Closed Tabs/Windows)?
Firefox can remember 3 closed windows as set via this pref on the about:config page.
- browser.sessionstore.max_windows_undo
- browser.sessionstore.max_tabs_undo
You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.
Backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data. Do NOT close Firefox when Firefox is already running.
You will normally find these files in the sessionstore-backups folder:
- previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
- recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
- recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
- upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)
You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file (make sure to backup the current sessionstore.jsonlz4).
You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.
- Help -> Troubleshooting Information -> Profile Directory:
Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder - http://kb.mozillazine.org/Profile_folder_-_Firefox
You can use this tool to inspect a compressed sessionstore file.
Thanks for your time cor-el! I can't wait to try it out first thing in the morning. (btw Recently Closed Windows was greyed out, so no luck there.)