Let's take an example.
In !3dprinting@lemmy.world sorting by "new", the most recent post I can see is "Planter head update". In MLem, or from the web interface of my instance, I can see 4 new posts !
I can't see a common feature about the invisible posts (posts of one particular user can be either seen or not, posts from one particular instance too, posts to one particular instance too...)
Strange thing : I CAN'T see any of my own post publishing a picture (from Arctic)
"Je ne le mange jamais" = Parfois, j'en trouve dans mon assiette, et je ne le mange pas.
Je pense que tu voulais dire "Je n'en ai jamais mangé" = Je n'ai jamais eu l'occasion d'en avoir dans mon assiette.