Discovered that utf8 chars are trimmed away from users StackExchange profiles usersupplied webpage url under bio.
E.g. for my case, the æ from my last name is getting trimmed, rendering the google+ url unusable (404). I assume utf8 to be accepted as of Name allow utf8, and when putting utf8 into the url field is the feedback not showing any warning or error, on the save of changes.
https://plus.google.com/+AndersFredrikUlvigKi%C3%A6r