lots of missing mobs, blocks & items

Just loaded up my snapshot world to find a lot of stuff missing.

Every passive mob in my village had vanished when I logged in, including all villagers, golems, tamed dogs & cats, penned sheep, cows, chickens, & rabbits. I checked a nearby village, and all entities there are missing as well.

All grass paths in the area have been removed. The wall behind the grey bed had about 7 maps from the surrounding area. They have vanished, along with the item frames.

Both natively generated and placed amethyst blocks as well as calcite & tuff are missing. Torches placed on a partially excavated geode now float in midair. All new geode & copper blocks have disappeared from chests, as well as a telescope.