Comment 5 for bug 1335618

As of Django 1.11, if some mandatory field(s) is not filled when a submit button is clicked, a message which suggest such field(s) are filled is shown based on 'required' attribute and the message is pop-ed by a modern browser like Chrome.
This is three years old and we fail to get an active assignee for a long time. Let's mark it as Incomplete so that the bug can be expired. Let's tackle it as a separate bug if filed.