For external storage on interface: make sure we override our handler supplier so we don't get network items as well (which leads to unstable behavior)

src/main/java/com/raoulvdberge/refinedstorage/apiimpl/network/node/NetworkNodeInterface.java

@@ -204,10 +204,14 @@ public class NetworkNodeInterface extends NetworkNode implements IComparable {
         return exportItems;
     }
 
-    public IItemHandler getItems() {
+    public IItemHandler getItemsOrNetworkItems() {
         return (itemsNetwork != null && exportSpecimenItems.isEmpty()) ? itemsNetwork : items;
     }
 
+    public IItemHandler getItems() {
+        return items;
+    }
+
     public IItemHandler getUpgrades() {
         return upgrades;
     }

src/main/java/com/raoulvdberge/refinedstorage/apiimpl/network/node/externalstorage/StorageItemItemHandler.java

@@ -6,6 +6,7 @@ import com.raoulvdberge.refinedstorage.apiimpl.API;
 import com.raoulvdberge.refinedstorage.tile.TileInterface;
 import com.raoulvdberge.refinedstorage.tile.config.IFilterable;
 import net.minecraft.item.ItemStack;
+import net.minecraft.tileentity.TileEntity;
 import net.minecraftforge.items.IItemHandler;
 import net.minecraftforge.items.ItemHandlerHelper;
 
@@ -24,7 +25,14 @@ public class StorageItemItemHandler extends StorageItemExternal {
     public StorageItemItemHandler(NetworkNodeExternalStorage externalStorage, Supplier<IItemHandler> handlerSupplier) {
         this.externalStorage = externalStorage;
         this.handlerSupplier = handlerSupplier;
-        this.connectedToInterface = externalStorage.getFacingTile() instanceof TileInterface;
+
+        TileEntity tile = externalStorage.getFacingTile();
+
+        if (tile instanceof TileInterface) {
+            // Make sure we override our handler supplier so we don't get network items as well (which leads to unstable behavior)
+            this.handlerSupplier = ((TileInterface) tile).getNode()::getItems;
+            this.connectedToInterface = true;
+        }
     }
 
     public boolean isConnectedToInterface() {

src/main/java/com/raoulvdberge/refinedstorage/tile/TileInterface.java

@@ -22,7 +22,7 @@ public class TileInterface extends TileNode<NetworkNodeInterface> {
     @Override
     public <T> T getCapability(@Nonnull Capability<T> capability, @Nullable EnumFacing facing) {
         if (capability == CapabilityItemHandler.ITEM_HANDLER_CAPABILITY) {
-            return CapabilityItemHandler.ITEM_HANDLER_CAPABILITY.cast(getNode().getItems());
+            return CapabilityItemHandler.ITEM_HANDLER_CAPABILITY.cast(getNode().getItemsOrNetworkItems());
         }
 
         return super.getCapability(capability, facing);