Remove Only-vanilla-biomes restriction (#1373)

worldedit-bukkit/adapters/adapter-1_17_1/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_17_R1_2/PaperweightFaweAdapter.java

@@ -608,11 +608,22 @@ public final class PaperweightFaweAdapter extends CachedBukkitAdapter implements
 
     @Override
     public int getInternalBiomeId(BiomeType biomeType) {
+        if (biomeType.getId().startsWith("minecraft:")) {
             Biome biomeBase = CraftBlock.biomeToBiomeBase(
                     MinecraftServer.getServer().registryAccess().ownedRegistryOrThrow(Registry.BIOME_REGISTRY),
                     BukkitAdapter.adapt(biomeType)
             );
             return MinecraftServer.getServer().registryAccess().ownedRegistryOrThrow(Registry.BIOME_REGISTRY).getId(biomeBase);
+        } else {
+            WritableRegistry<Biome> biomeRegistry = MinecraftServer.getServer().registryAccess()
+                    .ownedRegistryOrThrow(Registry.BIOME_REGISTRY);
+
+            ResourceLocation resourceLocation = biomeRegistry.keySet().stream()
+                    .filter(resource -> resource.toString().equals(biomeType.getId()))
+                    .findAny().orElse(null);
+
+            return biomeRegistry.getId(biomeRegistry.get(resourceLocation));
+        }
     }
 
     @Override