Fix lag when trying to right click items but the interaction fails

src/main/java/com/mitchej123/hodgepodge/config/FixesConfig.java

@@ -326,6 +326,11 @@ public class FixesConfig {
     @Config.RequiresMcRestart
     public static boolean fixWrongBlockPlacementDistanceCheck;
 
+    @Config.Comment("Fix inventory sync lag: prevents client to check recipes on empty slots. Particularly fixes lag when trying to eat food when full.")
+    @Config.DefaultBoolean(true)
+    @Config.RequiresMcRestart
+    public static boolean fixInventorySyncLag;
+
     /* ====== Minecraft fixes end ===== */
 
     // bukkit fixes

src/main/java/com/mitchej123/hodgepodge/mixins/Mixins.java

@@ -206,6 +206,9 @@ public enum Mixins {
                     "fml.MixinNetworkDispatcher",
                     "minecraft.NetworkManagerAccessor")
             .setApplyIf(() -> FixesConfig.fixBogusIntegratedServerNPEs).addTargetedMod(TargetedMod.VANILLA)),
+    FIX_LAG_ON_INVENTORY_SYNC(new Builder("Fix inventory sync lag").setPhase(Phase.EARLY)
+            .addMixinClasses("minecraft.MixinInventoryCrafting").setSide(Side.BOTH)
+            .setApplyIf(() -> FixesConfig.fixInventorySyncLag).addTargetedMod(TargetedMod.VANILLA)),
 
     FIX_LOGIN_DIMENSION_ID_OVERFLOW(
             new Builder("Fix dimension id overflowing when a player first logins on a server").setPhase(Phase.EARLY)

src/main/java/com/mitchej123/hodgepodge/mixins/early/minecraft/MixinInventoryCrafting.java

@@ -0,0 +1,23 @@
+package com.mitchej123.hodgepodge.mixins.early.minecraft;
+
+import net.minecraft.inventory.InventoryCrafting;
+import net.minecraft.item.ItemStack;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(InventoryCrafting.class)
+public class MixinInventoryCrafting {
+
+    @Shadow
+    private ItemStack[] stackList;
+
+    @Inject(method = "setInventorySlotContents", at = @At("HEAD"), cancellable = true)
+    public void setInventorySlotContents(int index, ItemStack stack, CallbackInfo ci) {
+        if (stack == null && this.stackList[index] == null) ci.cancel();
+    }
+
+}