@lain mastodon DOES have a limit for avatar - https://github.com/tootsuite/mastodon/blob/81c41d86814a3cc07baea2e1ff458aca6c374954/app/models/concerns/account_avatar.rb#L22 and it its 2.megabytes.

I kinda get the "feeling" how masto may be working, and probably it has same limit for user banner. Since pleroma doesn't scale any images uploaded to it, i used a largeass banner. So i guess when parsing my profile, it failed at validating banner (because it was too big) and it just fails completely - doesn't matter if other things pass the validation.

So i changed my banner to something smaller et voila.