fakruzaruret Also can people register their university mail via this extension? Does it accept only popular mail services?
A full listing of email providers that are blocked can be found here based on a quick look it appears to be 99% web domains known for heavy spamming. So far in my look I have not found any universities.
As far as locating users by email I do not belive that Flarum has anything built in for that, but you could possibly run an SQL query to find the user and then use their user ID to go to their Flarum URL (which would end up something like https://yourdomain.tld/u/<theirUserID>