Bukkit

I 'm using clearlag and Citizens

Yesterday I upgraded from version 2.8.4 to version 2.9.1

When used /lagg unloadchunks, npc's disappear

Spigot 1.8.8, clearlag 2.9.1, citizens 2.0.16

No errors in logs

Clearlag calls the ChunkUnloadEvent event before attempting to unload a chunk. If Citizens isn't listening to that event and handling it appropriately then it's a bug on their side.

You don't really have to use /unloadchunks on spigot either considering they deactivate entities, chunks, and so on when players aren't near them. Spigot should also be able to efficiently and silently unload the chunks it's self.

The only time i'd recommend using unloadchunks is when you're very low on memory and have no choice but to use it.

The "error" not happen in version 2.9.0.

In addition to NPC, also they disappeared animals and monsters.

@Seruhio18: Go

2.9.1 simply added an event before unloading the chunk for api.