Meta Box

OK. This seems to be working now. For anyone else interested...

• The 'role' select field is now created only when is_admin() == false - which fixes the duplication on the 'Edit User page.
• WordPress doesn't know anything about this 'role' select field - at least, not in relation to a user's roles and capabilities. Hence the need to use action rwmb_profile_after_process to find the just-saved 'role' meta_value in wp_usermeta and copy it across to 'wp_capabilities', which is where WordPress expects to find it.

  For the same reason, whenever we display the frontend form we need to ensure that the 'role' meta_value reflects the contents of 'wp_capabilities' - in case the user's role has been updated via the 'Edit User' page which doesn't update the 'role' meta_value.

• I'm using filters rwmb_user_login_html and rwmb_user_email_html to populate fields 'user_login' and 'user_email' based on $user_id. (For some reason, the corresponding rwmb_{$field_id}_field_meta filters don't seem to work for this.) I've also specified 'user_login' as 'disabled' => true, 'readonly' => true, 'save_field' => false - because it's not supposed to be changed.

Hope this helps someone.

Thanks - that's a very speedy and useful reply!

I think I've got enough here to make progress. Rather than manually adjusting user_id, I'll try including $user_id within do_shortcode()...

$form = "[mb_user_profile_info id='user_profile_role' user_id={$user_id}]";
echo do_shortcode( $form );

I'll let you know how I get on 🙂