I managed to track down how users can end up with a state where a collection is unable to be deleted as it is used in bindings.
Steps to repro:
- Create collection
- Add normal page
- Add collection list to page
- Add elements in the collection list. Bind to fields in the collection
- (optional?) Publish and unpublish site
- Delete normal page without deleting collection list first
- Now when you delete the collection, you need to request @staff for a “hard-refresh” on your site, or rollback to a previous save state before the collection was created.