It was a side-effect of the change to the userFilter; the pull-down beside it now auto-populates with a list of all users who have jobs in qube. This change benefits wranglers who often switch between different users, now they can just scroll down and pick the user from the list.
I see your point on this one, and will make the change so that re-enabling the user filter will use the last-used value, which is what a user who only manages their own jobs would do (all day long, like you say).
For now you can pick your name from the list, which is great if your username is Alex, not so hot if your name is William...