Paper/nms-patches/BlockSnow.patch

--- a/net/minecraft/server/BlockSnow.java
+++ b/net/minecraft/server/BlockSnow.java
@@ -58,6 +58,11 @@
     @Override
     public void tick(IBlockData iblockdata, World world, BlockPosition blockposition, Random random) {
         if (world.getBrightness(EnumSkyBlock.BLOCK, blockposition) > 11) {
+            // CraftBukkit start
+            if (org.bukkit.craftbukkit.event.CraftEventFactory.callBlockFadeEvent(world, blockposition, Blocks.AIR.getBlockData()).isCancelled()) {
+                return;
+            }
+            // CraftBukkit end
             c(iblockdata, world, blockposition);
             world.a(blockposition, false);
         }