Packet workaround

src/main/java/com/simibubi/create/content/schematics/client/SchematicHandler.java

@@ -12,9 +12,9 @@ import com.simibubi.create.content.schematics.SchematicWorld;
 import com.simibubi.create.content.schematics.client.tools.Tools;
 import com.simibubi.create.content.schematics.item.SchematicItem;
 import com.simibubi.create.content.schematics.packet.SchematicPlacePacket;
+import com.simibubi.create.content.schematics.packet.SchematicSyncPacket;
 import com.simibubi.create.foundation.gui.ToolSelectionScreen;
 import com.simibubi.create.foundation.networking.AllPackets;
-import com.simibubi.create.foundation.networking.NbtPacket;
 import com.simibubi.create.foundation.renderState.SuperRenderTypeBuffer;
 import com.simibubi.create.foundation.utility.outliner.AABBOutline;
 
@@ -272,17 +272,7 @@ public class SchematicHandler {
 	public void sync() {
 		if (activeSchematicItem == null)
 			return;
-
+		AllPackets.channel.sendToServer(new SchematicSyncPacket(activeHotbarSlot, transformation.toSettings(), transformation.getAnchor(), deployed));
-		PlacementSettings settings = transformation.toSettings();
-		CompoundNBT tag = activeSchematicItem.getTag();
-		tag.putBoolean("Deployed", deployed);
-		tag.put("Anchor", NBTUtil.writeBlockPos(transformation.getAnchor()));
-		tag.putString("Rotation", settings.getRotation()
-			.name());
-		tag.putString("Mirror", settings.getMirror()
-			.name());
-
-		AllPackets.channel.sendToServer(new NbtPacket(activeSchematicItem, activeHotbarSlot));
 	}
 
 	public void equip(Tools tool) {

src/main/java/com/simibubi/create/content/schematics/packet/SchematicSyncPacket.java

@@ -0,0 +1,77 @@
+package com.simibubi.create.content.schematics.packet;
+
+import java.util.function.Supplier;
+
+import com.simibubi.create.AllItems;
+import com.simibubi.create.foundation.networking.SimplePacketBase;
+
+import net.minecraft.entity.player.ServerPlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.nbt.CompoundNBT;
+import net.minecraft.nbt.NBTUtil;
+import net.minecraft.network.PacketBuffer;
+import net.minecraft.util.Mirror;
+import net.minecraft.util.Rotation;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.gen.feature.template.PlacementSettings;
+import net.minecraftforge.fml.network.NetworkEvent.Context;
+
+public class SchematicSyncPacket extends SimplePacketBase {
+
+	public int slot;
+	public boolean deployed;
+	public BlockPos anchor;
+	public Rotation rotation;
+	public Mirror mirror;
+
+	public SchematicSyncPacket(int slot, PlacementSettings settings,
+			BlockPos anchor, boolean deployed) {
+		this.slot = slot;
+		this.deployed = deployed;
+		this.anchor = anchor;
+		this.rotation = settings.getRotation();
+		this.mirror = settings.getMirror();
+	}
+
+	public SchematicSyncPacket(PacketBuffer buffer) {
+		slot = buffer.readVarInt();
+		deployed = buffer.readBoolean();
+		anchor = buffer.readBlockPos();
+		rotation = buffer.readEnumValue(Rotation.class);
+		mirror = buffer.readEnumValue(Mirror.class);
+	}
+
+	@Override
+	public void write(PacketBuffer buffer) {
+		buffer.writeVarInt(slot);
+		buffer.writeBoolean(deployed);
+		buffer.writeBlockPos(anchor);
+		buffer.writeEnumValue(rotation);
+		buffer.writeEnumValue(mirror);
+	}
+
+	@Override
+	public void handle(Supplier<Context> context) {
+		context.get().enqueueWork(() -> {
+			ServerPlayerEntity player = context.get().getSender();
+			if (player == null)
+				return;
+			ItemStack stack = ItemStack.EMPTY;
+			if (slot == -1) {
+				stack = player.getHeldItemMainhand();
+			} else {
+				stack = player.inventory.getStackInSlot(slot);
+			}
+			if (!AllItems.SCHEMATIC.isIn(stack)) {
+				return;
+			}
+			CompoundNBT tag = stack.getOrCreateTag();
+			tag.putBoolean("Deployed", deployed);
+			tag.put("Anchor", NBTUtil.writeBlockPos(anchor));
+			tag.putString("Rotation", rotation.name());
+			tag.putString("Mirror", mirror.name());
+		});
+		context.get().setPacketHandled(true);
+	}
+
+}

src/main/java/com/simibubi/create/foundation/networking/AllPackets.java

@@ -26,6 +26,7 @@ import com.simibubi.create.content.schematics.packet.ConfigureSchematicannonPack
 import com.simibubi.create.content.schematics.packet.InstantSchematicPacket;
 import com.simibubi.create.content.schematics.packet.SchematicPlacePacket;
 import com.simibubi.create.content.schematics.packet.SchematicUploadPacket;
+import com.simibubi.create.content.schematics.packet.SchematicSyncPacket;
 import com.simibubi.create.foundation.command.ConfigureConfigPacket;
 import com.simibubi.create.foundation.tileEntity.behaviour.filtering.FilteringCountUpdatePacket;
 import com.simibubi.create.foundation.tileEntity.behaviour.scrollvalue.ScrollValueUpdatePacket;
@@ -60,6 +61,7 @@ public enum AllPackets {
 	PLACE_ARM(ArmPlacementPacket.class, ArmPlacementPacket::new),
 	MINECART_COUPLING_CREATION(CouplingCreationPacket.class, CouplingCreationPacket::new),
 	INSTANT_SCHEMATIC(InstantSchematicPacket.class, InstantSchematicPacket::new),
+	SYNC_SCHEMATIC(SchematicSyncPacket.class, SchematicSyncPacket::new),
 
 	// Server to Client
 	SYMMETRY_EFFECT(SymmetryEffectPacket.class, SymmetryEffectPacket::new),

src/main/java/com/simibubi/create/foundation/networking/NbtPacket.java

@@ -2,12 +2,16 @@ package com.simibubi.create.foundation.networking;
 
 import java.util.function.Supplier;
 
+import com.simibubi.create.content.curiosities.symmetry.SymmetryWandItem;
+import com.simibubi.create.content.curiosities.zapper.ZapperItem;
+
 import net.minecraft.entity.player.ServerPlayerEntity;
 import net.minecraft.item.ItemStack;
 import net.minecraft.network.PacketBuffer;
 import net.minecraft.util.Hand;
 import net.minecraftforge.fml.network.NetworkEvent.Context;
 
+@Deprecated
 public class NbtPacket extends SimplePacketBase {
 
 	public ItemStack stack;
@@ -42,7 +46,10 @@ public class NbtPacket extends SimplePacketBase {
 			ServerPlayerEntity player = context.get().getSender();
 			if (player == null)
 				return;
-			
+			if (!(stack.getItem() instanceof SymmetryWandItem || stack.getItem() instanceof ZapperItem)) {
+				return;
+			}
+			stack.removeChildTag("AttributeModifiers");
 			if (slot == -1) {
 				ItemStack heldItem = player.getHeldItem(hand);
 				if (heldItem.getItem() == stack.getItem()) {