Jellyfin doesn't display favourites properly

[ThomasPGH]

Not in my case. In my case, going to the actual favourites behaves as I described above. There are currently 4 of my current 16 'eligible' movies showing.
https://imgur.com/a/LapNvlw

I don't know this screenshot as on all clients I've tried (Web interface, JMP, Android TV, Android, iPhone) the Favourites page doesn't look like in your screenshot.

I use Jellyfin For Kodi for most of my watching on the TV, which I have set up to show a list of all the Favourites on its home page. There, it shows that I've got 15-20 movies marked as favourite, where if I log onto Jellyfin, it only shows two.

So, you can see the favourites in Kodi but not with any other Jellyfin client?