Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing
Bukkit Changes:
39ce5d3a SPIGOT-4399: ItemMeta.equals broken with AttributeModifiers
CraftBukkit Changes:
1cf8b5dc SPIGOT-4400: Populators running on existing chunks
116cb9a1 SPIGOT-4399: Add attribute modifier equality test
5ee1c18a SPIGOT-4398: Set ASM7_EXPERIMENTAL flag
Minecraft is trying to set Dimension Objects based on a Dimension ID
Dimension ID's for custom worlds are dynamically allocate dand not guaranteed
consistent.
This removes checking the NBT data, as the Entity will always have its
DimensionManager set to the world it is being placed into.
This fixes corrupt entities breaking chunk saving in custom worlds.