WordPress registration process is based on the use of email. You can create your own registration page, and use fake random email just to fill the required email field, but you need to custom code registration process up to a point. How will you reach your users, if you have no way to contact them?
From WordPress Tavern – the article is for WordPress password-protected posts but the final paragraph reads: This update only affects password-protected posts. WordPress user passwords don’t share the same length restrictions and can be upwards of 1,000 characters long if so desired.
Not sure this is such a complex issue – WP provides an easy hook to control the email sent to the admin – wp_new_user_notification_email_admin you can read about the parameters here: https://developer.wordpress.org/reference/hooks/wp_new_user_notification_email_admin/ There is a “to” param, which allows you to define the email address to sent to, then it’s just a case of creating … Read more
So unfortunately without major revisions to both code and database structure this is not possible because WordPress stores the user email in a “UNIQUE” row in the database. Just unsetting the error message will not solve this issue because the user does not get created.
How can I find users that didn’t set a password?
This is a pretty basic solution. First I am assuming that you are not saving the data/form, and just returning to the same page.. In your $formContent you would do something like this. <?php $formContent=” …. <tr> <th><label for=”email”>Förnamn*</label></th> <td><input name=”first_name” id=”first_name” value=”” class=”regular-text” . $class_errors[‘first_name’] . ‘” type=”text”>’ . ( array_key_exists( ‘first_name’, $class_errors ) … Read more
There might be more elegant way to do it, but from quick look at the code it seems quite easy to simply override the relevant option on login page: add_action( ‘login_init’, function () { add_action( ‘pre_option_users_can_register’, ‘__return_null’ ); } );
This all depends on how users are being registered on your site. TLDR The code below allows you to create custom users from admin area specifying custom usernames, or use GENERATE_CUSTOM_SEQ_USERNAME to generate sequential numbered one. If using registration form other than wp-login.php just set user_login to GENERATE_CUSTOM_SEQ_USERNAME and hide the field using CSS. If … Read more
Password field (and confirmation) showing up twice on registration
http://wordpress.org/extend/plugins/wordpress-access-control/ seems to do what you need. You can probably also use http://wordpress.org/extend/plugins/role-scoper/ but it’s sort of complicated.