Φόρουμ κοινότητας «Firefox»

I recently made a backup (via the option under Account and sync in the settings), as I was switching to a new OS. Unfortunately, when selecting the backup in the new OS, I am greeted with the error message:

This file isn’t working. Try picking a different file.

According to this, my file is corrupted. Is there anything I can do to fix this, or have I just lost all my data? I no longer have access to the profile files in the original OS.

I run normal firefox on linux. Fully up-to-date. Every time I quit the app, it reverts to a version of my profile from a month ago, and loads all the tabs I had open then, and then receives all the tabs that I sent to the device in the interim (~1 month). As I speak, it just caught the 60 or 70 tabs in this window.

I tried changing the name of my profile folder to randomstring.defaultOLD and changed one of the backups to randomstring.default. This didn't change the behavior. I'm still stuck in the loop. I saved my tabs with onetab, because firefox isn't remembering my session anymore. I thought it was something to do with updates, like it only loses its mind upon updates, but that's not true. It thinks it's updating firefox EVERY TIME, because the one time it's loading to 1 month ago it was updating, but I'm 100% sure there are no updates to firefox in my linux. It's just hallucinating.

The articles on restoring from backup are outdated. They say to use an html file. There is no html file. It's just folders for profiles, not html files. HELP!