The Community Site has management buttons that you can see in collections you don't own. For example, these buttons or controls may change the thumbnail of a collection, removing one project from a collection, or editing the description of a collection. These don't work if you're not the collection owner.
Notice the dashed outline. It means it is editable. Just it could not be edited actually.
This is technically a website bug that could be fixed by making those buttons and controls not visible or editable.