Steps:

1. Go to Admin/Content Types
2. Create new Content Type Group
3. Mark checkbox from new Content Type Group as checked - Trash button is active
4. Click, for example, Users tab
5. Click browser back button

Actual result:

Checkbox is marked as checked, but Trash button is disabled. User has to uncheck and check again to activate Trash button.

Expected result:

Trash button is active.