display_name is not updated if javascript is disabled

[elmll]

If one has javascript disabled the display name is not updated if the users changes his name. Also plugins that provide user credentials and update the users entry in the database can not determine the users display_name setting.

The display_name field should only hold a reference to the style how the name is displayed. That way no javascript would be needed to set the display_name and also plugins can change the users credentials without producing inconsistency or forcing a style for the display name.

[c3mdigital]

This condition would only happen if you tried to change your display name at the same time you added or changed your first or last name. On page refresh the select option list contains all variations and can be selected and saved without javascript.