If an input error was detected due to a blank input on a required field, the user is informed of the fields which were left blank in the error message.
During manual evaluation, when testing webforms, leave the entire form blank and submit. Any required fields that were left blank need to be detailed within the error message that is received.
(For details on valid error messages, refer to Guideline 78: Whenever an input error is detected through validation, the user is informed of the error, and what was incorrect in the input.)
