Set the browser to emulate a very slow connection, so it's easier to check this bug.
Steps to reproduce:
- Go to Content > Forms
- Add a Form
- Add a new Field
While the field settings don't show up, a loading animation should be displayed to give users a feedback. Also, the change field type option should not be clickable OR displayed.
The sidebar opens and remains blank for a while. Also, if you click in the change field type option, it will seem cut (because the blank div will be in front of the dropdown).