I have run across this biome now on two different servers, and in both cases it has consistently caused me to drop from ~60 FPS to <20, getting down around 8 when using only a couple of profiling/informational mods along with it. (TickProfiler, TellMe etc). I've flown around in creative for about half an hour and seen no other comparable FPS drops, but TPing back into the area or flying into it from nearby sees my FPS immediately plummet. A separate PC in the house has the same issue.

Using the seed 'josacd' will spawn you right next to a Floating Plains with a village in it. The frame rate is always worst for me at sea level or below, and at its very worst when first entering the area. When it does eventually stabilize, it's higher than the sub-20 FPS I see at first, but significantly worse than my consistent 60+ everywhere else.

I have this problem too, I'm not running a fantastic PC but normally I get FPS from 60-80 range but under those islands or when first spawning them they plummet to a 15-25 range. has anyone figured out a way of stopping this? or at least maybe a way of stopping the floating biomes from spawning in the first place?