Limit User Name Characters when Registering

jwack,

Here is a good place to start: https://scriptplayground.com/tutorials/js/Limit-Textfield-Input/. If the maxlength attribute wasn’t depreciated this would be easier.

This information corresponds to the wp-login.php file at line 415.

jwack,

Adding maxlength=”9″ in wp-login.php at line 415 worked for me. Now my new users are limited to a username no longer than nine characters.

just remember ya did that! You’ll lose that change on every upgrade