invisible chests/shulkers with FRPC: On

[Koko8574]

My chests & shulkers still appear invisible sometimes even with "Force Ressource Pack Compatibility" turned on.
Here is the only texture pack I use if this could help:
VanillaTweaks1.21.3.x.zip
Also, when I reload the texture pack (F3+T) the blocks arent longer invisible, but they are again if I launch minecraft again.