[Os'es:] So far I've noticed this on Windows10 and Ubuntu 16.04 consoles. (53/52) [Description:] Console warnings and errors shown while Password manager is being used. [Steps:] 1. Open FF. 2. Open any http page. 3. Save a few logins. 4. Reload the http page and pick an u/p. 5. Check console output. Actual Result: Contextual warning message is displayed. U/p are filled in. Console: 1. " console.warn: nsLoginManager: searchLogins: `formSubmitURL` or `httpRealm` is recommended" (i've got this in windows 10 as well as in Ubuntu 16.04 but I didn't catch the exact moment when this is thrown) 2. ERROR - ContextualIdentityService - Unknown version found in /home/adrian.florinescu/.mozilla/firefox/xfac2i83.az2s/containers.json (I'm guessing it might be related to the fact that I've run 51 with a profile created on 53) Expected Result: There should be no console errors/warnings.

I can't reproduce this on OS X. I added the warning so know what it's about and I suspect it's harmless but would still like to understand what changed.