"Please fill in Display Name "
Receiving this error in the Customer Registration, Edit Shipping Address page. You just have to go into the page, even if you do not edit a field, clicking the save button gets this error.
Only modification is Css to not show the Suffix input field.
Suffix is not set as a required field and the error occurs with this Css line active or not
#centerpage [name=ShipSuffix] { display: none; }