Username and Authentication Questions
Is the Username/Email case-sensitive?
No the Username/Email is converted to lower case when a new user is created because emails are not case-sensitive.
Will it work if a user tries to log in with capital letters in their Username/Email?
Yes, their username will be taken as lower case even if they type in capital letters.
Can you have several users in the system with a same email address?
No, the email address is the user's unique identifier and username so there cannot be duplicates...