add support for non-supported bags/packs. If there is no compat layer yet for a bag/pack item from a mod, then attempt to place that bag into your hotbar and simulate a right click to open it. Prefer empty slots, non-tool slots, non-food slots if it needs to swap for something currently on your hotbar.

src/main/java/com/trunksbomb/bagtabs/bag/BagAccess.java

@@ -21,7 +21,7 @@ public final class BagAccess {
                 BagIdentityData.ensureBagId(stack);
             }
             BagCompat.BagHandler handler = BagCompat.findHandler(stack);
-            if (handler != null) {
+            if (handler != null || BagCompat.canShowInTabs(stack)) {
                 bags.add(new BagEntry(slot, stack.copy(), handler, BagCompat.getIdentity(stack)));
             }
         }

src/main/java/com/trunksbomb/bagtabs/bag/BagCompat.java

@@ -50,6 +50,10 @@ public final class BagCompat {
         return !stack.isEmpty() && (findHandler(stack) != null || looksLikeInventoryItem(stack));
     }
 
+    public static boolean canShowInTabs(ItemStack stack) {
+        return canName(stack);
+    }
+
     public static BagIdentity getIdentity(ItemStack stack) {
         if (!canName(stack)) {
             return null;

src/main/java/com/trunksbomb/bagtabs/network/OpenBagPayload.java

@@ -2,13 +2,27 @@ package com.trunksbomb.bagtabs.network;
 
 import com.trunksbomb.bagtabs.BagTabs;
 import com.trunksbomb.bagtabs.bag.BagCompat;
-import com.trunksbomb.bagtabs.bag.InventoryBag;
+import net.minecraft.core.component.DataComponents;
 import net.minecraft.network.RegistryFriendlyByteBuf;
 import net.minecraft.network.codec.ByteBufCodecs;
 import net.minecraft.network.codec.StreamCodec;
 import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
+import net.minecraft.network.protocol.game.ClientboundSetCarriedItemPacket;
 import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.InteractionResult;
+import net.minecraft.world.entity.player.Inventory;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.BlockItem;
+import net.minecraft.world.item.BowItem;
+import net.minecraft.world.item.CrossbowItem;
+import net.minecraft.world.item.DiggerItem;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ProjectileWeaponItem;
+import net.minecraft.world.item.ShearsItem;
+import net.minecraft.world.item.ShieldItem;
+import net.minecraft.world.item.SwordItem;
+import net.minecraft.world.item.TridentItem;
 import net.neoforged.neoforge.network.handling.IPayloadContext;
 
 public record OpenBagPayload(int slot) implements CustomPacketPayload {
@@ -37,6 +51,99 @@ public record OpenBagPayload(int slot) implements CustomPacketPayload {
         BagCompat.BagHandler handler = BagCompat.findHandler(stack);
         if (handler != null) {
             handler.open(serverPlayer, payload.slot(), stack);
+            return;
+        }
+
+        if (BagCompat.canShowInTabs(stack)) {
+            if (!openViaHotbarFallback(serverPlayer, payload.slot())) {
+                serverPlayer.sendSystemMessage(BagTabs.translation("generic_open_failed"));
+                BagTabs.LOGGER.debug("Failed to open bag fallback for item {} in slot {}", stack, payload.slot());
+            }
         }
     }
+
+    private static boolean openViaHotbarFallback(ServerPlayer player, int sourceSlot) {
+        Inventory inventory = player.getInventory();
+        ItemStack sourceStack = inventory.getItem(sourceSlot);
+        if (sourceStack.isEmpty()) {
+            return false;
+        }
+
+        int targetHotbarSlot = chooseHotbarSlot(inventory, sourceSlot);
+        if (targetHotbarSlot < 0) {
+            return false;
+        }
+
+        if (sourceSlot != targetHotbarSlot) {
+            ItemStack hotbarStack = inventory.getItem(targetHotbarSlot).copy();
+            inventory.setItem(targetHotbarSlot, sourceStack.copy());
+            inventory.setItem(sourceSlot, hotbarStack);
+        }
+
+        inventory.selected = targetHotbarSlot;
+        player.connection.send(new ClientboundSetCarriedItemPacket(targetHotbarSlot));
+        player.inventoryMenu.broadcastChanges();
+
+        ItemStack mainHandStack = player.getItemInHand(InteractionHand.MAIN_HAND);
+        if (mainHandStack.isEmpty()) {
+            return false;
+        }
+
+        int previousContainerId = player.containerMenu.containerId;
+        InteractionResult result = player.gameMode.useItem(player, player.level(), mainHandStack, InteractionHand.MAIN_HAND);
+        player.inventoryMenu.broadcastChanges();
+        return result.consumesAction() || player.containerMenu.containerId != previousContainerId;
+    }
+
+    private static int chooseHotbarSlot(Inventory inventory, int sourceSlot) {
+        if (sourceSlot >= 0 && sourceSlot < Inventory.getSelectionSize()) {
+            return sourceSlot;
+        }
+
+        for (int hotbarSlot = 0; hotbarSlot < Inventory.getSelectionSize(); hotbarSlot++) {
+            if (inventory.getItem(hotbarSlot).isEmpty()) {
+                return hotbarSlot;
+            }
+        }
+
+        for (int hotbarSlot = 0; hotbarSlot < Inventory.getSelectionSize(); hotbarSlot++) {
+            if (isBuildingBlock(inventory.getItem(hotbarSlot))) {
+                return hotbarSlot;
+            }
+        }
+
+        for (int hotbarSlot = 0; hotbarSlot < Inventory.getSelectionSize(); hotbarSlot++) {
+            if (isPreferredMiscItem(inventory.getItem(hotbarSlot))) {
+                return hotbarSlot;
+            }
+        }
+
+        return -1;
+    }
+
+    private static boolean isBuildingBlock(ItemStack stack) {
+        return !stack.isEmpty() && stack.getItem() instanceof BlockItem && !isTorch(stack.getItem());
+    }
+
+    private static boolean isPreferredMiscItem(ItemStack stack) {
+        if (stack.isEmpty()) {
+            return false;
+        }
+        Item item = stack.getItem();
+        return !stack.has(DataComponents.FOOD)
+                && !isTorch(item)
+                && !(item instanceof DiggerItem)
+                && !(item instanceof SwordItem)
+                && !(item instanceof BowItem)
+                && !(item instanceof CrossbowItem)
+                && !(item instanceof TridentItem)
+                && !(item instanceof ShieldItem)
+                && !(item instanceof ShearsItem)
+                && !(item instanceof ProjectileWeaponItem);
+    }
+
+    private static boolean isTorch(Item item) {
+        return item instanceof BlockItem blockItem
+                && blockItem.getBlock().getDescriptionId().toLowerCase(java.util.Locale.ROOT).contains("torch");
+    }
 }

src/main/resources/assets/bagtabs/lang/en_us.json

@@ -36,6 +36,7 @@
   "bagtabs.dock.side.screen_right": "Dock: Screen Right",
   "bagtabs.dock.side.floating_horizontal": "Dock: Floating Horizontal",
   "bagtabs.dock.side.floating_vertical": "Dock: Floating Vertical",
+  "bagtabs.generic_open_failed": "No safe hotbar slot was available to open that bag.",
   "key.categories.bagtabs": "Bag Tabs",
   "key.bagtabs.open_last_bag": "Open Last Bag"
 }