Comment 6 for bug 1595620

It's most likely one of the empathy accounts, because IIRC all other account plugins use OAuth, whose re-authentication screen looks very different from this.

It's very strange that this happened: when signon-ui is requested to show a dialog, it shows it only if it's given a X window ID to parent it to; otherwise, no dialog is shown and you'll see an OSD notification instead. Unless it was unable to dispatch the message to the indicator.

Can you please check if "com.canonical.indicators.webcredentials" is an active (or activatable) D-Bus service in your session (you could use d-feet for this)?