working 1.20.6

platforms/mixin-common/src/main/resources/terra.accesswidener

@@ -1,4 +1,4 @@
 accessWidener v1 named
 accessible class net/minecraft/world/biome/Biome$Weather
 accessible class net/minecraft/world/gen/WorldPresets$Registrar
-accessible method net/minecraft/block/FluidBlock getFluidState (Lnet/minecraft/block/BlockState;)Lnet/minecraft/fluid/FluidState
+accessible class net/minecraft/registry/RegistryLoader$Loader

platforms/mixin-common/src/main/resources/terra.common.mixins.json

@@ -2,7 +2,7 @@
     "required": true,
     "minVersion": "0.8",
     "package": "com.dfsek.terra.mod.mixin",
-    "compatibilityLevel": "JAVA_17",
+    "compatibilityLevel": "JAVA_21",
     "mixins": [
         "access.BiomeAccessor",
         "access.MobSpawnerLogicAccessor",