“Your password can have at least one cyrillic character” WTF XD
But you know what the worst part was?
They never bothered informing you about these limitations. The site just returned a generic error.
Not supporting special characters I can kinda understand but silently discarding characters from the password the user has picked is just evil. It took me LOTS of registration attempts and password resets before I figured out what the hell was going on.
IIRC this is mostly done to prevent SQL injection attacks. In a modern system there is 0 reason not to allow any characters in the password (within whatever encoding you support).
Sure enough, different parts of the site had different password requirements, and they enforced them on password change. So you could create an account on a sub-site that wasn't accepted on the main site, which was the only site with the password change page, but you couldn't enter the old password to fix it.
I think password reset did work, but I wound up creating another password that worked in one place but not another...
I saw a screenshot of an error dialogue on Reddit once (so possibly fake, but still hilarious) that said something like:
"You cannot use that password, because it's already in use by user Kegstand360"