I am also having this problem. The inside of my mob farm, after a few minutes will show a light level of 15 in one chunk while the next is complete darkness
[media]I've had a similar problem in my single player. Extreme lag loading chunks and lags mobs all over like on a server. Changing settings doesnt help, neither did more ram. Loading chunks drop my frames worse than having 100+ mods installed. Vanilla 1.14 = Chunk loading lag
Had this happen on two separate occasions in the same world. Trader Llamas have been on my island for many days, not despawning
Still having this problem in pre-release 2.
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