unsure how related this is, but i just encountered an invisible witch in 1.16.4. video here
singleplayer 1.16.4, running optifine. resource pack is vanilla tweaks, and a custom one that only changes a few paintings. world is running a datapack that edits only mob loot tables and recipes
MC-205916
Can confirm this happened to worlds hosted on Realms in 1.15.2, haven't seen it in the month since then but may still affect Realms worlds
unsure how related this is, but i just encountered an invisible witch in 1.16.4. video here
singleplayer 1.16.4, running optifine. resource pack is vanilla tweaks, and a custom one that only changes a few paintings. world is running a datapack that edits only mob loot tables and recipes