Remove Unused Assets not (yet) working

When I open a file, there is a Missing Assets message popping up. The assets listed are showing up in the Unused Assets list but not in the Asset Manager. On the contrary, there are medias in the Manager which are not used in the project (in the yellow square on the screenshot) but don’t show up neither as missing nor unused. I understand these are in the Blocs app ressource folder to be used in the project and as such, cannot be deleted. That’s why they don’t display in the unused assets list. Nevertheless it is not clear for users.

But the main problem is why Missing Assets display items which are not used and why Unused Assets are not in the All Assets Manager. The medias listed in Missing or Unused are clearly items from the original template I used.

A precision: I deleted unused assets but still, when reopening the file, the Missing Assets still list few which are not in Unused nor in Asset Manager.