Auto-save runs when no changes in Display option of Content Area

Description

Steps to reproduce:
Precondition: Edit a published page of Content Area property having a content item (Item1) displayed in "Automatic" option.

1. Open the context menu of Item1 in Content Area.
2. Click Display > Automatic option.
3. Click outside the property.

Expected:
Auto-saving is not run. New draft version is not created.

Actual:
Auto-saving runs, and a new draft version is created with no content differences.