Installed the game on MultiMC, with no additional mods except for Optifine and was using AdaptOpenJDK as my Java Runtime.

Tried multiple reinstallations but I can never seem to craft the Grass Fiber Mesh. Also some items which are supposed to be locked back in 3.0.8 are unlocked in the tutorial stage.

I'm going to guess you're using the OpenJ9 VM. This is a known incompatibility, you can use OpenJDK but only the HotSpot VM is compatible.

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