Page Slots do not show the primary class applied to them in the navigator. They always appear as “Page Slot” which is unlike all other elements. This is very confusing and requires you to click on them to determine their class and there is no way to tell them apart.

You could argue that there should only be one page slot per page, but there’s nothing preventing you from adding more than one and applying different classes to them, so there should be a way to tell them apart.