Firefox launches with empty session

This started happening like a week ago or so, I originally had Cachy Browser installed and it was restoring my session and saving my cookies as I like, then all of a sudden it started launching in an empty session everytime and deleting all my cookies etc. I’ve checked and rechecked all the obvious Settings, I’ve deleted ~/.cache/mozilla and ~/.mozilla and nothing. I even deleted Cachy Browser and just installed upstream Firefox, same issues…

Any ideas?

Have you tried a new profile in Firefox?
Do you have any extensions installed?

Creating a new profile helped - until I logged back into my account. I’ve tried deleting and redeleting and refreshing etc. in about:support in between signing out and creating profiles and nothing…

Deleted all my extensions as well as disabled them. Seems like it’s something bugged with my cloud account sync? I’ve also tried disabling history, tabs and settings syncing but still no dice…

edit: I might have fixed it? Do I have any idea how? Of course not. Last thing I did was:

  1. uncheck sync history, tabs and settings from sync,
  2. close browser,
  3. open profile manager delete all profiles
  4. create a new one,
  5. test that one a bit before installing extensions (still haven’t signed in),
  6. go into my account on mozilla.com and logout of all sessions
  7. login to my account in browser
  8. ???
  9. seems to be working.

Extremely weird and annoying. I suspect if it was multi-account containers somehow, it wouldn’t be the first time I’ve had bizarre issues with that add-on, maybe it was trying to sync tabs with an old session or something causing firefox to barf on startup? Who knows, I’ve removed multi-account containers we’ll see if it comes back.

Good to hear it’s sorted.
I think you’re right about it referencing another session - perhaps it was trying to pull from the other session and either finding nothing, or there is nothing to find.
I’ve not had any issues with multi-account containers, but I also don’t sync the same thing as you do, so it would be good to test that theory further.