On wet farmland there is no texture, when placing farmland it may be instant or take a few minutes but it will turn into a missing texture block. 

As far as I have looked into it goes back to 1.15.2 for me. This all started after the migration of  my account and the only way I can actually get textures is if I use optifine.

Being in a world that has these missing textures make my game lag and on some occasions just shut the game