l create a content type which has a field of entity_reference, called field_user, the widgets type is autocomplete, target type is user,and I create a views display attached, and set it as required.
when I input existed user's keyword, field_user can search out user and node save is OK.
But when input user's keyword which no user has such keyword, the views behind entity_reference attached have no result return,this is fine,but the wrong keyword which I input in autocomplete widgtes text is still there. as field_user is not empty(staticsfied with required) so when I submit the node it' created suceefully even didn't check the field_user is valid or not.
after the node saved, I found that there is no field_user value show,it's still empty.
why entity_reference didn't clean up input of autocomplete when there is no result return and raise an error when submited?