Quoted from "Entoarox"
Seems that its acting like TreeCapitator Fun times.
Do the blocks themselves still remain, but just invisible? If so, please give the coordinates and angles it happens at, since that would mean invisible render chunks, and since it doesnt happen to everyone everywhere its likely an issue with the math that becomes noticeable at those coordinates.
Happens everywhere. Double checked to make sure Optifine wasnt the cause by removing it from the instance, Still happened. It was rather hilarious and I found it amusing. And, yes, the blocks still remain, just the top portion of the tree is gone, theyre just invisible for some reason. Wasn't able to identify what option could influence it.
I am having the exact same problem. Custom server running forge-1.7.10-10.13.4.1492-1.7.10-universal.jar and Forge Essentials 126.96.36.1992 with Sliptopia modpack. FE states specifically it conflicts with FastCraft 1.21 so I'm using 1.22ctest13 but having the same problem with it not rendering the world, though it also seems to be just the tops of trees and then only some of them. It also fails to render about 90% of the Advent of Ascension dimensions as well. Blocks are there but invisible or not "synced" with the client. You get rubberbanding and "xxx has moved incorrectly" errors. Looking forward to a possible fix! I've had to disable FastCraft and there is a very noticeable difference in new chunk generation with and without it.