Paper/nms-patches/EnchantmentFrostWalker.patch

--- a/net/minecraft/server/EnchantmentFrostWalker.java
+++ b/net/minecraft/server/EnchantmentFrostWalker.java
@@ -1,6 +1,10 @@
 package net.minecraft.server;
 
 import java.util.Iterator;
+// CraftBukkit start
+import org.bukkit.craftbukkit.util.CraftMagicNumbers;
+import org.bukkit.event.block.EntityBlockFormEvent;
+// CraftBukkit end
 
 public class EnchantmentFrostWalker extends Enchantment {
 
@@ -41,8 +45,11 @@
                         IBlockData iblockdata2 = world.getType(blockposition1);
 
                         if (iblockdata2.getMaterial() == Material.WATER && (Integer) iblockdata2.get(BlockFluids.LEVEL) == 0 && iblockdata.canPlace(world, blockposition1) && world.a(iblockdata, blockposition1, VoxelShapeCollision.a())) {
-                            world.setTypeUpdate(blockposition1, iblockdata);
-                            world.getBlockTickList().a(blockposition1.immutableCopy(), Blocks.FROSTED_ICE, MathHelper.nextInt(entityliving.getRandom(), 60, 120));
+                            // CraftBukkit Start - Call EntityBlockFormEvent for Frost Walker
+                            if (org.bukkit.craftbukkit.event.CraftEventFactory.handleBlockFormEvent(world, blockposition1, iblockdata, entityliving)) {
+                                world.getBlockTickList().a(blockposition1.immutableCopy(), Blocks.FROSTED_ICE, MathHelper.nextInt(entityliving.getRandom(), 60, 120));
+                            }
+                            // CraftBukkit End
                         }
                     }
                 }