Inconsistent behavior of the protection against leaving without saving when editing application pages or the title of 'regular' pages

How to reproduce:

• go to an application page (e.g. one of the movies from the movie application from the standard help module)
• enter edit mode by clicking the edit button of the page (not by editing the properties one by one)
• in the edit form that is displayed, change all sorts of values including at least one of the rich text editors
• navigate away from the page - click on any link, or hit back of the browser of anything
• a browser alert / popup will be displayed, asking if you're sure you want to leave the page
  • this feature corresponds to CKEDITOR-18 , if I'm not wrong
• cancel the edit form, enter edit form again (do the same step as above)
• this time, modify any other field in the form, except for the rich text editor(s)
• navigate away from the page

Expected behavior:

• a browser alert / popup will be displayed, asking if you're sure you want to leave the page

Actual behaviour:

• no question is asked, the browser navigates away, the changes are lost.

The protection of against leaving without saving seems to be bound to the Rich text editor (CKEditor) and restricted to its changes instead of being bound to all the visible fields of the form.
Note: because of this being bound to the rich text editor, this problem also applies to the editing of a page's title without touching its content, in regular Wysiwyg mode and in Inplace editing mode.