This is a strange user interface for creating user.
Where the form says “username” : When i provide an email address, the JavaScript rejects anything with special characters. So i used a username : John
But then when I try to log in with the username, it rejects the credentials.
However, if i use the “email address” associated with John, as username it works.
Am i doing something wrong?
if i am not mistaken the ‘username’ is just the display name (as seen in the upper right when logged in) while u need the email in the authentification process.
Maybe ‘user name’ is more like user’s name
Thanks vrms! So, username is an “alias” and has nothing to do with the login credentials. Not sure who can confirm. 
also the username is also used in messaging where you can get another users attention with @username which is probably a lot quicker than using their full email address
That might be it. That is the functionality of it. Still guessing eh Thanks Julian!