diff --git a/mappings/net/minecraft/item/ItemGroup.mapping b/mappings/net/minecraft/item/ItemGroup.mapping
index 99111c2b16..c7e2fd3ba6 100644
--- a/mappings/net/minecraft/item/ItemGroup.mapping
+++ b/mappings/net/minecraft/item/ItemGroup.mapping
@@ -5,6 +5,8 @@ CLASS net/minecraft/class_1761 net/minecraft/item/ItemGroup
 	COMMENT @see Item#appendStacks
 	COMMENT @see Item#isIn(ItemGroup)
 	FIELD field_26391 displayName Lnet/minecraft/class_2561;
+	FIELD field_40184 displayStacks Lnet/minecraft/class_7708;
+	FIELD field_40185 searchTabStacks Lnet/minecraft/class_7708;
 	FIELD field_7917 renderName Z
 	FIELD field_7919 texture Ljava/lang/String;
 	FIELD field_7920 scrollbar Z
@@ -12,6 +14,16 @@ CLASS net/minecraft/class_1761 net/minecraft/item/ItemGroup
 	FIELD field_7934 icon Lnet/minecraft/class_1799;
 	METHOD <init> (ILnet/minecraft/class_2561;)V
 		ARG 1 index
+		ARG 2 displayName
+	METHOD method_45410 getDisplayStacks (Lnet/minecraft/class_7699;)Lnet/minecraft/class_7708;
+	METHOD method_45411 addItems (Lnet/minecraft/class_7699;Lnet/minecraft/class_1761$class_7704;)V
+		ARG 2 adder
+	METHOD method_45412 contains (Lnet/minecraft/class_7699;Lnet/minecraft/class_1799;)Z
+		ARG 2 stack
+	METHOD method_45413 getStacks (Lnet/minecraft/class_7699;Z)Lnet/minecraft/class_7708;
+		ARG 2 search
+	METHOD method_45414 getSearchTabStacks (Lnet/minecraft/class_7699;)Lnet/minecraft/class_7708;
+	METHOD method_45415 clearStacks ()V
 	METHOD method_7737 getDisplayName ()Lnet/minecraft/class_2561;
 	METHOD method_7741 getIndex ()I
 	METHOD method_7742 getTexture ()Ljava/lang/String;
@@ -30,3 +42,30 @@ CLASS net/minecraft/class_1761 net/minecraft/item/ItemGroup
 		COMMENT <p>The name is rendered below the top row of item groups and above the inventory.
 	METHOD method_7755 isTopRow ()Z
 	METHOD method_7756 hasScrollbar ()Z
+	CLASS class_7703 BasicStackAdder
+		FIELD field_40187 parentTabStacks Lnet/minecraft/class_7708;
+		FIELD field_40188 searchTabStacks Lnet/minecraft/class_7708;
+		FIELD field_40189 group Lnet/minecraft/class_1761;
+		METHOD <init> (Lnet/minecraft/class_1761;Lnet/minecraft/class_7699;)V
+			ARG 1 group
+		METHOD method_45416 getParentTabStacks ()Lnet/minecraft/class_7708;
+		METHOD method_45418 getSearchTabStacks ()Lnet/minecraft/class_7708;
+	CLASS class_7704 StackAdder
+		METHOD method_45417 add (Lnet/minecraft/class_1799;Lnet/minecraft/class_1761$class_7705;)V
+			ARG 1 stack
+			ARG 2 visibiity
+		METHOD method_45419 (Lnet/minecraft/class_1761$class_7705;Lnet/minecraft/class_1799;)V
+			ARG 2 stack
+		METHOD method_45420 add (Lnet/minecraft/class_1799;)V
+			ARG 1 stack
+		METHOD method_45421 add (Lnet/minecraft/class_1935;)V
+			ARG 1 item
+		METHOD method_45422 add (Lnet/minecraft/class_1935;Lnet/minecraft/class_1761$class_7705;)V
+			ARG 1 item
+			ARG 2 visibility
+		METHOD method_45423 addAll (Ljava/util/Collection;)V
+			ARG 1 stacks
+		METHOD method_45424 addAll (Ljava/util/Collection;Lnet/minecraft/class_1761$class_7705;)V
+			ARG 1 stacks
+			ARG 2 visibility
+	CLASS class_7705 StackVisibility
diff --git a/mappings/net/minecraft/item/ItemGroups.mapping b/mappings/net/minecraft/item/ItemGroups.mapping
new file mode 100644
index 0000000000..8635e5c2db
--- /dev/null
+++ b/mappings/net/minecraft/item/ItemGroups.mapping
@@ -0,0 +1,35 @@
+CLASS net/minecraft/class_7706 net/minecraft/item/ItemGroups
+	FIELD field_40195 BUILDING_BLOCKS Lnet/minecraft/class_1761;
+	FIELD field_40196 NATURE Lnet/minecraft/class_1761;
+	FIELD field_40197 FUNCTIONAL Lnet/minecraft/class_1761;
+	FIELD field_40198 REDSTONE Lnet/minecraft/class_1761;
+	FIELD field_40199 HOTBAR Lnet/minecraft/class_1761;
+	FIELD field_40200 SEARCH Lnet/minecraft/class_1761;
+	FIELD field_40201 TOOLS Lnet/minecraft/class_1761;
+	FIELD field_40202 COMBAT Lnet/minecraft/class_1761;
+	FIELD field_40203 CONSUMABLES Lnet/minecraft/class_1761;
+	FIELD field_40204 CRAFTING Lnet/minecraft/class_1761;
+	FIELD field_40205 SPAWN_EGGS Lnet/minecraft/class_1761;
+	FIELD field_40206 INVENTORY Lnet/minecraft/class_1761;
+	FIELD field_40207 GROUPS [Lnet/minecraft/class_1761;
+	METHOD method_45426 addInstruments (Lnet/minecraft/class_1761$class_7704;Lnet/minecraft/class_1792;Lnet/minecraft/class_6862;Lnet/minecraft/class_1761$class_7705;)V
+		ARG 0 adder
+		ARG 1 item
+		ARG 2 instrumentTag
+		ARG 3 visibility
+	METHOD method_45427 addPotions (Lnet/minecraft/class_1761$class_7704;Lnet/minecraft/class_1792;Lnet/minecraft/class_1761$class_7705;)V
+		ARG 0 adder
+		ARG 1 item
+		ARG 2 visibility
+	METHOD method_45428 addMaxLevelEnchantedBooks (Lnet/minecraft/class_1761$class_7704;Ljava/util/Set;Lnet/minecraft/class_1761$class_7705;)V
+		ARG 0 adder
+		ARG 1 targets
+		ARG 2 visibility
+	METHOD method_45429 asArray ([Lnet/minecraft/class_1761;)[Lnet/minecraft/class_1761;
+		ARG 0 groups
+	METHOD method_45430 addAllLevelEnchantedBooks (Lnet/minecraft/class_1761$class_7704;Ljava/util/Set;Lnet/minecraft/class_1761$class_7705;)V
+		ARG 0 adder
+		ARG 1 targets
+		ARG 2 visibility
+	CLASS 2
+		FIELD field_40208 ENCHANTMENT_TARGETS Ljava/util/Set;
diff --git a/mappings/net/minecraft/item/ItemStackSet.mapping b/mappings/net/minecraft/item/ItemStackSet.mapping
new file mode 100644
index 0000000000..0b0c68de5f
--- /dev/null
+++ b/mappings/net/minecraft/item/ItemStackSet.mapping
@@ -0,0 +1,8 @@
+CLASS net/minecraft/class_7708 net/minecraft/item/ItemStackSet
+	FIELD field_40212 HASH_STRATEGY Lit/unimi/dsi/fastutil/Hash$Strategy;
+	CLASS 1
+		METHOD equals (Ljava/lang/Object;Ljava/lang/Object;)Z
+			ARG 1 first
+			ARG 2 second
+		METHOD hashCode (Ljava/lang/Object;)I
+			ARG 1 stack