There is an option to pick up photo during registration:
But if I click on Pick a photo button, then instead of dialog of selecting photo some strange block is shown:
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Oh hey, now there's an oversight that's gone unnoticed for several weeks. :/
Sorry about that. I pushed a fix, but there are a few other changes waiting to go to production in the pipe right now and some of them look scary, so I'm gonna do my Saturday night a favor and wait till Monday to deploy.
In the meantime, you should be able to edit your photo from your profile.