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While playing around with a fresh installation of 18.04, I've accidentally selected a photo for my user. I couldn't find an undo or cancel or remove option, so now I'm stuck with a photo on the login screen. Is there any way to return to the default faceless gray avatar?
My workaround would be to create a new user, grab a screenshot, cut the default image and use that as my new "photo" but if there's a real removal option I'd love to know about it.
Update: I did not take a photo with the webcam, just selected one of the provided images, so there is no .face file in my home directory.