um_validation_safe_username_regex not allowing me to restrict additional chars?

I’m trying to use the um_validation_safe_username_regex filter (see below) to limit registration usernames only to alphanumeric characters. I’m enacting it as a Snippet and activating it. But Ultimate Member is allowing users to continue registering with the dashes, spaces, underscores, etc.

function um_custom_validation_safe_username( $regex_safe ) {
return $regex_safe;
add_filter( 'um_validation_safe_username_regex', 'um_custom_validation_safe_username', 10, 1 );

Does this filter only add additional characters to allow, or can it be used to further restrict? I don’t understand why it’s not working.

  • This topic was modified 22 minutes ago by rando390.


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