bug 644898 is saying to warn the user about this happening. this bug is about changing that behavior. it's clearly unexpected that this would occur. app settings are not same as web site settings, so are not expected to be cleared. here are the steps (with screenshots) that a user went through when setting up credentials which leads to this: https://twitter.com/#!/maxart/status/135910621949595648.

Hi! Here are the Privacy settings I am using, with which my Sync setup gets erased every time I restart Firefox/Aurora/Nightly: http://cl.ly/0C3P1n111C3m0R0j2i22 Which means, as Dietrich mentioned, that every time I restart Firefox, I need to re-setup Sync, to log back in my account, and keep my Bookmarks in sync: 1: http://cl.ly/1N3B2t2E3a3x1f3w0A0C (Connect - as I already have an account) 2: http://cl.ly/3Y3F0S3N0B452x001y0j (I don't have the device with me) 3: http://cl.ly/4538393S0l0b390D3C40 (fill in credentials and Continue) Basically what I would like, as a user, is to be able to delete everything when Firefox closes (Cookies, Active Logins, Passwords, History, Site Preferences, Cache, Offline Data, etc.) WITHOUT affecting Sync, so I don't need to re-login my Sync account every time. I hope this helps clarify the issue. Best, Max @maxart

(In reply to Dietrich Ayala (:dietrich) from comment #0) > this bug is about changing that behavior. it's clearly unexpected that this > would occur. app settings are not same as web site settings, so are not > expected to be cleared. I wouldn't use the word "clearly". If a user sets "Firefox will… clear passwords" (which has no mention of website settings, just "data"), they could quite reasonably expect that this includes their Sync credentials. After all, with those credentials they could get back all the data we just cleared, right? It's by no means obvious what the correct behavior is here. Maybe we need to add another category to clear-on-exit, named "Firefox Sync credentials". At the very least we need to get some concrete information about user expectations here. This has come up a few times over the aeons (Bug 667574, Bug 553400), so I'm going to dupe this back. Bug 644898 is a different take on this, so I'll leave that as NEW.