When ever the user does a load, save, diff (, other?) action with the server, we should check for whether the new edit token is an anonymous one when we're expecting the user to be logged in, so we can warn the user that they're now logged out (to prevent them asking for their IP to be over-sighted, etc.).
There's potentially utility in doing this in core (for the wikitext editor) as well.
Version: unspecified
Severity: enhancement