1. Control Panel> Web Content
2. Add [Basic Web Content]
Results: there are fields without headings, and values in these fields will not be saved (DefaultWC.png).
1. Control Panel> Web Content: Structure
2. Add Structure xxx with Title, Body
3. Add Web Content selecting that Structure
4. Next to Structure: xxx, click [Edit]
Results: All fields will have the message [This field is required] though the "required" option isn't checked (Structure.png). Web Content can still be published even if these fields are not filled.
In edit mode, the Form Controls, Application Fields etc are not usable. It is difficult to edit structure.