1791202 - After deleting your Firefox profile folder, Firefox refuses to start (but perhaps should offer to create a new profile, or pick a different profile).

Status: RESOLVED DUPLICATE of bug 1551773

(Toolkit :: Startup and Profile System, defect)

Description

[Daniel Holbert [:dholbert]]

STR (which I just performed on Windows 10):

1. In your file explorer, delete the folders associated with your default Firefox profile. In particular:

$HOME/AppData/Local/Mozilla/Firefox/Profiles/{your-profile-name}
$HOME/AppData/Roaming/Mozilla/Firefox/Profiles/{your-profile-name}

(In my case, I did this by accident, thinking I was cleaning up some data from an old/no-longer-used browser profile.)

2. Try to start Firefox e.g. by clicking on your toolbar icon.

ACTUAL RESULTS:
A Firefox skeleton window appears, and then a dialog appears saying

Profile missing
Your firefox profile cannot be loaded. It may be missing or inaccessible.
[OK]

And there's no clear way to make Firefox ever work again.

EXPECTED RESULTS:
Some path to get back to a working state (e.g. an offer to create a new profile or to choose another Firefox profile).

e.g. we could have a button for "Launch Profile Manager" or something like that?

Comment 1

[Daniel Holbert [:dholbert]]

Version info: I'm using up-to-date Nightly 106.

I was able to get back to a working state by manually editing my desktop Nightly shortcut, to add -ProfileManager at the end of the Target field, so that it says "path/to/firefox.exe" -ProfileManager. This let me launch the profile manager so that I could create a new default profile.

But we should probably add some more user-discoverable route to get back to a working state here which doesn't require knowing how to do that. Otherwise users just end up with Firefox being indefinitely non-functional with no clear way to recover (other than maybe (?) an uninstall+reinstall loop).

Comment 2

[BugBot [:suhaib / :marco]]

The Bugbug bot thinks this bug should belong to the 'Toolkit::Startup and Profile System' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.