Heavily improve changed item display.

OtterGui

@@ -1 +1 @@
-Subproject commit 3bf047bfa293817a691b7f06032bae7aeb2e4dc7
+Subproject commit c347d29d980b0191d1d071170cf2ec229e3efdcf

Penumbra.GameData

@@ -1 +1 @@
-Subproject commit bc339208d1d453582eb146533c572823146a4592
+Subproject commit 955c4e6b281bf0781689b15c01a868b0de5881b4

Penumbra/Api/Api/UiApi.cs

@@ -81,21 +81,21 @@ public class UiApi : IPenumbraApiUi, IApiService, IDisposable
     public void CloseMainWindow()
         => _configWindow.IsOpen = false;
 
-    private void OnChangedItemClick(MouseButton button, IIdentifiedObjectData? data)
+    private void OnChangedItemClick(MouseButton button, IIdentifiedObjectData data)
     {
         if (ChangedItemClicked == null)
             return;
 
-        var (type, id) = data?.ToApiObject() ?? (ChangedItemType.None, 0);
+        var (type, id) = data.ToApiObject();
         ChangedItemClicked.Invoke(button, type, id);
     }
 
-    private void OnChangedItemHover(IIdentifiedObjectData? data)
+    private void OnChangedItemHover(IIdentifiedObjectData data)
     {
         if (ChangedItemTooltip == null)
             return;
 
-        var (type, id) = data?.ToApiObject() ?? (ChangedItemType.None, 0);
+        var (type, id) = data.ToApiObject();
         ChangedItemTooltip.Invoke(type, id);
     }
 }

Penumbra/Api/ModChangedItemAdapter.cs

@@ -65,7 +65,7 @@ public sealed class ModChangedItemAdapter(WeakReference<ModStorage> storage)
             : throw new ObjectDisposedException("The underlying mod storage of this IPC container was disposed.");
     }
 
-    private sealed class ChangedItemDictionaryAdapter(SortedList<string, IIdentifiedObjectData?> data) : IReadOnlyDictionary<string, object?>
+    private sealed class ChangedItemDictionaryAdapter(SortedList<string, IIdentifiedObjectData> data) : IReadOnlyDictionary<string, object?>
     {
         public IEnumerator<KeyValuePair<string, object?>> GetEnumerator()
             => data.Select(d => new KeyValuePair<string, object?>(d.Key, d.Value?.ToInternalObject())).GetEnumerator();

Penumbra/Collections/Cache/CollectionCache.cs

@@ -23,7 +23,7 @@ public sealed class CollectionCache : IDisposable
     private readonly CollectionCacheManager                                          _manager;
     private readonly ModCollection                                                   _collection;
     public readonly  CollectionModData                                               ModData       = new();
-    private readonly SortedList<string, (SingleArray<IMod>, IIdentifiedObjectData?)> _changedItems = [];
+    private readonly SortedList<string, (SingleArray<IMod>, IIdentifiedObjectData)> _changedItems = [];
     public readonly  ConcurrentDictionary<Utf8GamePath, ModPath>                     ResolvedFiles = new();
     public readonly  CustomResourceCache                                             CustomResources;
     public readonly  MetaCache                                                       Meta;
@@ -43,7 +43,7 @@ public sealed class CollectionCache : IDisposable
     private int _changedItemsSaveCounter = -1;
 
     // Obtain currently changed items. Computes them if they haven't been computed before.
-    public IReadOnlyDictionary<string, (SingleArray<IMod>, IIdentifiedObjectData?)> ChangedItems
+    public IReadOnlyDictionary<string, (SingleArray<IMod>, IIdentifiedObjectData)> ChangedItems
     {
         get
         {
@@ -441,7 +441,7 @@ public sealed class CollectionCache : IDisposable
             // Skip IMCs because they would result in far too many false-positive items,
             // since they are per set instead of per item-slot/item/variant.
             var identifier = _manager.MetaFileManager.Identifier;
-            var items      = new SortedList<string, IIdentifiedObjectData?>(512);
+            var items      = new SortedList<string, IIdentifiedObjectData>(512);
 
             void AddItems(IMod mod)
             {

Penumbra/Collections/ModCollection.Cache.Access.cs

@@ -46,8 +46,8 @@ public partial class ModCollection
     internal IReadOnlyDictionary<Utf8GamePath, ModPath> ResolvedFiles
         => _cache?.ResolvedFiles ?? new ConcurrentDictionary<Utf8GamePath, ModPath>();
 
-    internal IReadOnlyDictionary<string, (SingleArray<IMod>, IIdentifiedObjectData?)> ChangedItems
+    internal IReadOnlyDictionary<string, (SingleArray<IMod>, IIdentifiedObjectData)> ChangedItems
-        => _cache?.ChangedItems ?? new Dictionary<string, (SingleArray<IMod>, IIdentifiedObjectData?)>();
+        => _cache?.ChangedItems ?? new Dictionary<string, (SingleArray<IMod>, IIdentifiedObjectData)>();
 
     internal IEnumerable<SingleArray<ModConflicts>> AllConflicts
         => _cache?.AllConflicts ?? Array.Empty<SingleArray<ModConflicts>>();

Penumbra/Communication/ChangedItemClick.cs

@@ -12,7 +12,7 @@ namespace Penumbra.Communication;
 ///     <item>Parameter is the clicked object data if any. </item>
 /// </list>
 /// </summary>
-public sealed class ChangedItemClick() : EventWrapper<MouseButton, IIdentifiedObjectData?, ChangedItemClick.Priority>(nameof(ChangedItemClick))
+public sealed class ChangedItemClick() : EventWrapper<MouseButton, IIdentifiedObjectData, ChangedItemClick.Priority>(nameof(ChangedItemClick))
 {
     public enum Priority
     {

Penumbra/Communication/ChangedItemHover.cs

@@ -10,7 +10,7 @@ namespace Penumbra.Communication;
 ///     <item>Parameter is the hovered object data if any. </item>
 /// </list>
 /// </summary>
-public sealed class ChangedItemHover() : EventWrapper<IIdentifiedObjectData?, ChangedItemHover.Priority>(nameof(ChangedItemHover))
+public sealed class ChangedItemHover() : EventWrapper<IIdentifiedObjectData, ChangedItemHover.Priority>(nameof(ChangedItemHover))
 {
     public enum Priority
     {

Penumbra/Meta/Manipulations/AtchIdentifier.cs

@@ -31,7 +31,7 @@ public readonly record struct AtchIdentifier(AtchType Type, GenderRace GenderRac
     public override string ToString()
         => $"Atch - {Type.ToAbbreviation()} - {GenderRace.ToName()} - {EntryIndex}";
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         // Nothing specific
     }

Penumbra/Meta/Manipulations/Eqdp.cs

@@ -15,7 +15,7 @@ public readonly record struct EqdpIdentifier(PrimaryId SetId, EquipSlot Slot, Ge
     public Gender Gender
         => GenderRace.Split().Item1;
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
         => identifier.Identify(changedItems, GamePaths.Mdl.Equipment(SetId, GenderRace, Slot));
 
     public MetaIndex FileIndex()

Penumbra/Meta/Manipulations/Eqp.cs

@@ -8,7 +8,7 @@ namespace Penumbra.Meta.Manipulations;
 
 public readonly record struct EqpIdentifier(PrimaryId SetId, EquipSlot Slot) : IMetaIdentifier, IComparable<EqpIdentifier>
 {
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
         => identifier.Identify(changedItems, GamePaths.Mdl.Equipment(SetId, GenderRace.MidlanderMale, Slot));
 
     public MetaIndex FileIndex()

Penumbra/Meta/Manipulations/Est.cs

@@ -24,17 +24,17 @@ public readonly record struct EstIdentifier(PrimaryId SetId, EstType Slot, Gende
     public Gender Gender
         => GenderRace.Split().Item1;
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         switch (Slot)
         {
             case EstType.Hair:
-                changedItems.TryAdd(
+                changedItems.UpdateCountOrSet(
-                    $"Customization: {GenderRace.Split().Item2.ToName()} {GenderRace.Split().Item1.ToName()} Hair {SetId}", null);
+                    $"Customization: {GenderRace.Split().Item2.ToName()} {GenderRace.Split().Item1.ToName()} Hair {SetId}", () => new IdentifiedName());
                 break;
             case EstType.Face:
-                changedItems.TryAdd(
+                changedItems.UpdateCountOrSet(
-                    $"Customization: {GenderRace.Split().Item2.ToName()} {GenderRace.Split().Item1.ToName()} Face {SetId}", null);
+                    $"Customization: {GenderRace.Split().Item2.ToName()} {GenderRace.Split().Item1.ToName()} Face {SetId}", () => new IdentifiedName());
                 break;
             case EstType.Body:
                 identifier.Identify(changedItems, GamePaths.Mdl.Equipment(SetId, GenderRace, EquipSlot.Body));

Penumbra/Meta/Manipulations/GlobalEqpManipulation.cs

@@ -70,7 +70,7 @@ public readonly struct GlobalEqpManipulation : IMetaIdentifier
     public override string ToString()
         => $"Global EQP - {Type}{(Condition != 0 ? $" - {Condition.Id}" : string.Empty)}";
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         var path = Type switch
         {
@@ -86,9 +86,9 @@ public readonly struct GlobalEqpManipulation : IMetaIdentifier
         if (path.Length > 0)
             identifier.Identify(changedItems, path);
         else if (Type is GlobalEqpType.DoNotHideVieraHats)
-            changedItems["All Hats for Viera"] = null;
+            changedItems.UpdateCountOrSet("All Hats for Viera", () => new IdentifiedName());
         else if (Type is GlobalEqpType.DoNotHideHrothgarHats)
-            changedItems["All Hats for Hrothgar"] = null;
+            changedItems.UpdateCountOrSet("All Hats for Hrothgar", () => new IdentifiedName());
     }
 
     public MetaIndex FileIndex()

Penumbra/Meta/Manipulations/Gmp.cs

@@ -8,7 +8,7 @@ namespace Penumbra.Meta.Manipulations;
 
 public readonly record struct GmpIdentifier(PrimaryId SetId) : IMetaIdentifier, IComparable<GmpIdentifier>
 {
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
         => identifier.Identify(changedItems, GamePaths.Mdl.Equipment(SetId, GenderRace.MidlanderMale, EquipSlot.Head));
 
     public MetaIndex FileIndex()

Penumbra/Meta/Manipulations/IMetaIdentifier.cs

@@ -19,7 +19,7 @@ public enum MetaManipulationType : byte
 
 public interface IMetaIdentifier
 {
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems);
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems);
 
     public MetaIndex FileIndex();
 

Penumbra/Meta/Manipulations/Imc.cs

@@ -27,10 +27,10 @@ public readonly record struct ImcIdentifier(
         : this(primaryId, variant, slot.IsAccessory() ? ObjectType.Accessory : ObjectType.Equipment, 0, slot, BodySlot.Unknown)
     { }
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
         => AddChangedItems(identifier, changedItems, false);
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems, bool allVariants)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems, bool allVariants)
     {
         var path = ObjectType switch
         {

Penumbra/Meta/Manipulations/Rsp.cs

@@ -8,8 +8,8 @@ namespace Penumbra.Meta.Manipulations;
 
 public readonly record struct RspIdentifier(SubRace SubRace, RspAttribute Attribute) : IMetaIdentifier
 {
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
-        => changedItems.TryAdd($"{SubRace.ToName()} {Attribute.ToFullString()}", null);
+        => changedItems.UpdateCountOrSet($"{SubRace.ToName()} {Attribute.ToFullString()}", () => new IdentifiedName());
 
     public MetaIndex FileIndex()
         => MetaIndex.HumanCmp;

Penumbra/Mods/Groups/CombiningModGroup.cs

@@ -136,7 +136,7 @@ public sealed class CombiningModGroup : IModGroup
     public void AddData(Setting setting, Dictionary<Utf8GamePath, FullPath> redirections, MetaDictionary manipulations)
         => Data[setting.AsIndex].AddDataTo(redirections, manipulations);
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         foreach (var container in DataContainers)
             identifier.AddChangedItems(container, changedItems);

Penumbra/Mods/Groups/IModGroup.cs

@@ -53,7 +53,7 @@ public interface IModGroup
     public IModGroupEditDrawer EditDrawer(ModGroupEditDrawer editDrawer);
 
     public void AddData(Setting setting, Dictionary<Utf8GamePath, FullPath> redirections, MetaDictionary manipulations);
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems);
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems);
 
     /// <summary> Ensure that a value is valid for a group. </summary>
     public Setting FixSetting(Setting setting);

Penumbra/Mods/Groups/ImcModGroup.cs

@@ -131,7 +131,7 @@ public class ImcModGroup(Mod mod) : IModGroup
         }
     }
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
         => Identifier.AddChangedItems(identifier, changedItems, AllVariants);
 
     public Setting FixSetting(Setting setting)

Penumbra/Mods/Groups/MultiModGroup.cs

@@ -122,7 +122,7 @@ public sealed class MultiModGroup(Mod mod) : IModGroup, ITexToolsGroup
         }
     }
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         foreach (var container in DataContainers)
             identifier.AddChangedItems(container, changedItems);

Penumbra/Mods/Groups/SingleModGroup.cs

@@ -107,7 +107,7 @@ public sealed class SingleModGroup(Mod mod) : IModGroup, ITexToolsGroup
         OptionData[setting.AsIndex].AddDataTo(redirections, manipulations);
     }
 
-    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData?> changedItems)
+    public void AddChangedItems(ObjectIdentification identifier, IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         foreach (var container in DataContainers)
             identifier.AddChangedItems(container, changedItems);

Penumbra/Mods/Manager/ModCacheManager.cs

@@ -139,6 +139,7 @@ public class ModCacheManager : IDisposable, IService
             mod.ChangedItems.RemoveMachinistOffhands();
 
         mod.LowerChangedItemsString = string.Join("\0", mod.ChangedItems.Keys.Select(k => k.ToLowerInvariant()));
+        ++mod.LastChangedItemsUpdate;
     }
 
     private static void UpdateCounts(Mod mod)

Penumbra/Mods/Mod.cs

@@ -101,13 +101,14 @@ public sealed class Mod : IMod
     }
 
     // Cache
-    public readonly SortedList<string, IIdentifiedObjectData?> ChangedItems = new();
+    public readonly SortedList<string, IIdentifiedObjectData> ChangedItems = new();
 
     public string LowerChangedItemsString { get; internal set; } = string.Empty;
     public string AllTagsLower            { get; internal set; } = string.Empty;
 
-    public int  TotalFileCount     { get; internal set; }
+    public int    TotalFileCount         { get; internal set; }
-    public int  TotalSwapCount     { get; internal set; }
+    public int    TotalSwapCount         { get; internal set; }
-    public int  TotalManipulations { get; internal set; }
+    public int    TotalManipulations     { get; internal set; }
+    public ushort LastChangedItemsUpdate { get; internal set; }
     public bool HasOptions         { get; internal set; }
 }

Penumbra/UI/AdvancedWindow/ResourceTreeViewer.cs

@@ -25,7 +25,6 @@ public class ResourceTreeViewer(
     private const ResourceTreeFactory.Flags ResourceTreeFactoryFlags =
         ResourceTreeFactory.Flags.RedactExternalPaths | ResourceTreeFactory.Flags.WithUiData | ResourceTreeFactory.Flags.WithOwnership;
 
-    private readonly CommunicatorService _communicator = communicator;
     private readonly HashSet<nint>       _unfolded     = [];
 
     private readonly Dictionary<nint, NodeVisibility> _filterCache = [];
@@ -278,7 +277,7 @@ public class ResourceTreeViewer(
                 if (ImGui.IsItemClicked())
                     ImGui.SetClipboardText(resourceNode.FullPath.ToPath());
                 if (hasMod && ImGui.IsItemClicked(ImGuiMouseButton.Right) && ImGui.GetIO().KeyCtrl)
-                    _communicator.SelectTab.Invoke(TabType.Mods, mod);
+                    communicator.SelectTab.Invoke(TabType.Mods, mod);
 
                 ImGuiUtil.HoverTooltip(
                     $"{resourceNode.FullPath.ToPath()}\n\nClick to copy to clipboard.{(hasMod ? "\nControl + Right-Click to jump to mod." : string.Empty)}{GetAdditionalDataSuffix(resourceNode.AdditionalData)}");

Penumbra/UI/ChangedItemDrawer.cs

@@ -9,6 +9,7 @@ using OtterGui;
 using OtterGui.Classes;
 using OtterGui.Raii;
 using OtterGui.Services;
+using OtterGui.Text;
 using Penumbra.Api.Enums;
 using Penumbra.GameData.Data;
 using Penumbra.Services;
@@ -86,18 +87,20 @@ public class ChangedItemDrawer : IDisposable, IUiService
     }
 
     /// <summary> Check if a changed item should be drawn based on its category. </summary>
-    public bool FilterChangedItem(string name, IIdentifiedObjectData? data, LowerString filter)
+    public bool FilterChangedItem(string name, IIdentifiedObjectData data, LowerString filter)
         => (_config.Ephemeral.ChangedItemFilter == ChangedItemFlagExtensions.AllFlags
              || _config.Ephemeral.ChangedItemFilter.HasFlag(data.GetIcon().ToFlag()))
          && (filter.IsEmpty || !data.IsFilteredOut(name, filter));
 
     /// <summary> Draw the icon corresponding to the category of a changed item. </summary>
-    public void DrawCategoryIcon(IIdentifiedObjectData? data)
+    public void DrawCategoryIcon(IIdentifiedObjectData data, float height)
-        => DrawCategoryIcon(data.GetIcon().ToFlag());
+        => DrawCategoryIcon(data.GetIcon().ToFlag(), height);
 
     public void DrawCategoryIcon(ChangedItemIconFlag iconFlagType)
+        => DrawCategoryIcon(iconFlagType, ImGui.GetFrameHeight());
+
+    public void DrawCategoryIcon(ChangedItemIconFlag iconFlagType, float height)
     {
-        var height = ImGui.GetFrameHeight();
         if (!_icons.TryGetValue(iconFlagType, out var icon))
         {
             ImGui.Dummy(new Vector2(height));
@@ -114,50 +117,50 @@ public class ChangedItemDrawer : IDisposable, IUiService
         }
     }
 
-    /// <summary>
+    public void ChangedItemHandling(IIdentifiedObjectData data, bool leftClicked)
-    /// Draw a changed item, invoking the Api-Events for clicks and tooltips.
-    /// Also draw the item ID in grey if requested.
-    /// </summary>
-    public void DrawChangedItem(string name, IIdentifiedObjectData? data)
     {
-        name = data?.ToName(name) ?? name;
+        var ret = leftClicked ? MouseButton.Left : MouseButton.None;
-        using (ImRaii.PushStyle(ImGuiStyleVar.SelectableTextAlign, new Vector2(0,               0.5f))
+        ret = ImGui.IsItemClicked(ImGuiMouseButton.Right) ? MouseButton.Right : ret;
-                   .Push(ImGuiStyleVar.ItemSpacing, new Vector2(ImGui.GetStyle().ItemSpacing.X, ImGui.GetStyle().CellPadding.Y * 2)))
+        ret = ImGui.IsItemClicked(ImGuiMouseButton.Middle) ? MouseButton.Middle : ret;
-        {
+        if (ret != MouseButton.None)
-            var ret = ImGui.Selectable(name, false, ImGuiSelectableFlags.None, new Vector2(0, ImGui.GetFrameHeight()))
+            _communicator.ChangedItemClick.Invoke(ret, data);
-                ? MouseButton.Left
+        if (!ImGui.IsItemHovered())
-                : MouseButton.None;
+            return;
-            ret = ImGui.IsItemClicked(ImGuiMouseButton.Right) ? MouseButton.Right : ret;
-            ret = ImGui.IsItemClicked(ImGuiMouseButton.Middle) ? MouseButton.Middle : ret;
-            if (ret != MouseButton.None)
-                _communicator.ChangedItemClick.Invoke(ret, data);
-        }
 
-        if (_communicator.ChangedItemHover.HasTooltip && ImGui.IsItemHovered())
+        using var tt = ImUtf8.Tooltip();
-        {
+        if (data.Count == 1)
-            // We can not be sure that any subscriber actually prints something in any case.
+            ImUtf8.Text("This item is changed through a single effective change.\n");
-            // Circumvent ugly blank tooltip with less-ugly useless tooltip.
+        else
-            using var tt = ImRaii.Tooltip();
+            ImUtf8.Text($"This item is changed through {data.Count} distinct effective changes.\n");
-            using (ImRaii.Group())
+        ImGui.SetCursorPosY(ImGui.GetCursorPosY() + 3 * ImUtf8.GlobalScale);
-            {
+        ImGui.Separator();
-                _communicator.ChangedItemHover.Invoke(data);
+        ImGui.SetCursorPosY(ImGui.GetCursorPosY() + 3 * ImUtf8.GlobalScale);
-            }
+        _communicator.ChangedItemHover.Invoke(data);
-
-            if (ImGui.GetItemRectSize() == Vector2.Zero)
-                ImGui.TextUnformatted("No actions available.");
-        }
     }
 
     /// <summary> Draw the model information, right-justified. </summary>
-    public static void DrawModelData(IIdentifiedObjectData? data)
+    public static void DrawModelData(IIdentifiedObjectData data, float height)
     {
-        var additionalData = data?.AdditionalData ?? string.Empty;
+        var additionalData = data.AdditionalData;
         if (additionalData.Length == 0)
             return;
 
-        ImGui.SameLine(ImGui.GetContentRegionAvail().X);
+        ImGui.SameLine();
-        ImGui.AlignTextToFramePadding();
+        using var color = ImRaii.PushColor(ImGuiCol.Text, ColorId.ItemId.Value());
-        ImGuiUtil.RightJustify(additionalData, ColorId.ItemId.Value());
+        ImGui.SetCursorPosY(ImGui.GetCursorPosY() + (height - ImGui.GetTextLineHeight()) / 2);
+        ImUtf8.TextRightAligned(additionalData, ImGui.GetStyle().ItemInnerSpacing.X);
+    }
+
+    /// <summary> Draw the model information, right-justified. </summary>
+    public static void DrawModelData(ReadOnlySpan<byte> text, float height)
+    {
+        if (text.Length == 0)
+            return;
+
+        ImGui.SameLine();
+        using var color = ImRaii.PushColor(ImGuiCol.Text, ColorId.ItemId.Value());
+        ImGui.SetCursorPosY(ImGui.GetCursorPosY() + (height - ImGui.GetTextLineHeight()) / 2);
+        ImUtf8.TextRightAligned(text, ImGui.GetStyle().ItemInnerSpacing.X);
     }
 
     /// <summary> Draw a header line with the different icon types to filter them. </summary>
@@ -276,7 +279,7 @@ public class ChangedItemDrawer : IDisposable, IUiService
         return true;
     }
 
-    private static unsafe IDalamudTextureWrap? LoadUnknownTexture(IDataManager gameData, ITextureProvider textureProvider)
+    private static IDalamudTextureWrap? LoadUnknownTexture(IDataManager gameData, ITextureProvider textureProvider)
     {
         var unk = gameData.GetFile<TexFile>("ui/uld/levelup2_hr1.tex");
         if (unk == null)

Penumbra/UI/ModsTab/ModPanelChangedItemsTab.cs

@@ -1,47 +1,268 @@
+using Dalamud.Interface;
+using Dalamud.Interface.Utility.Raii;
 using ImGuiNET;
 using OtterGui;
 using OtterGui.Classes;
-using OtterGui.Raii;
 using OtterGui.Services;
+using OtterGui.Text;
 using OtterGui.Widgets;
 using Penumbra.GameData.Data;
+using Penumbra.GameData.Enums;
+using Penumbra.GameData.Structs;
+using Penumbra.Mods;
+using Penumbra.String;
 
 namespace Penumbra.UI.ModsTab;
 
-public class ModPanelChangedItemsTab(ModFileSystemSelector selector, ChangedItemDrawer drawer) : ITab, IUiService
+public class ModPanelChangedItemsTab(
+    ModFileSystemSelector selector,
+    ChangedItemDrawer drawer,
+    ImGuiCacheService cacheService,
+    EphemeralConfig config)
+    : ITab, IUiService
 {
+    private readonly ImGuiCacheService.CacheId _cacheId = cacheService.GetNewId();
+
+    private class ChangedItemsCache
+    {
+        private         Mod?                _lastSelected;
+        private         ushort              _lastUpdate;
+        private         ChangedItemIconFlag _filter = ChangedItemFlagExtensions.DefaultFlags;
+        private         bool                _reset;
+        public readonly List<Container>     Data = [];
+        public          bool                AnyExpandable { get; private set; }
+
+        public record struct Container
+        {
+            public IIdentifiedObjectData Data;
+            public ByteString            Text;
+            public ByteString            ModelData;
+            public uint                  Id;
+            public int                   Children;
+            public ChangedItemIconFlag   Icon;
+            public bool                  Expandable;
+            public bool                  Expanded;
+            public bool                  Child;
+
+            public static Container Single(string text, IIdentifiedObjectData data)
+                => new()
+                {
+                    Child      = false,
+                    Text       = ByteString.FromStringUnsafe(data.ToName(text),   false),
+                    ModelData  = ByteString.FromStringUnsafe(data.AdditionalData, false),
+                    Icon       = data.GetIcon().ToFlag(),
+                    Expandable = false,
+                    Expanded   = false,
+                    Data       = data,
+                    Id         = 0,
+                    Children   = 0,
+                };
+
+            public static Container Parent(string text, IIdentifiedObjectData data, uint id, int children, bool expanded)
+                => new()
+                {
+                    Child      = false,
+                    Text       = ByteString.FromStringUnsafe(data.ToName(text),   false),
+                    ModelData  = ByteString.FromStringUnsafe(data.AdditionalData, false),
+                    Icon       = data.GetIcon().ToFlag(),
+                    Expandable = true,
+                    Expanded   = expanded,
+                    Data       = data,
+                    Id         = id,
+                    Children   = children,
+                };
+
+            public static Container Indent(string text, IIdentifiedObjectData data)
+                => new()
+                {
+                    Child      = true,
+                    Text       = ByteString.FromStringUnsafe(data.ToName(text),           false),
+                    ModelData  = ByteString.FromStringUnsafe(data.AdditionalData, false),
+                    Icon       = data.GetIcon().ToFlag(),
+                    Expandable = false,
+                    Expanded   = false,
+                    Data       = data,
+                    Id         = 0,
+                    Children   = 0,
+                };
+        }
+
+        public void Reset()
+            => _reset = true;
+
+        public void Update(Mod? mod, ChangedItemDrawer drawer, ChangedItemIconFlag filter)
+        {
+            if (mod == _lastSelected && _lastSelected!.LastChangedItemsUpdate == _lastUpdate && _filter == filter && !_reset)
+                return;
+
+            _reset = false;
+            Data.Clear();
+            AnyExpandable = false;
+            _lastSelected = mod;
+            _filter       = filter;
+            if (_lastSelected == null)
+                return;
+
+            _lastUpdate = _lastSelected.LastChangedItemsUpdate;
+            var tmp = new Dictionary<(PrimaryId, FullEquipType), List<IdentifiedItem>>();
+
+            foreach (var (s, i) in _lastSelected.ChangedItems)
+            {
+                if (i is not IdentifiedItem item)
+                    continue;
+
+                if (!drawer.FilterChangedItem(s, item, LowerString.Empty))
+                    continue;
+
+                if (tmp.TryGetValue((item.Item.PrimaryId, item.Item.Type), out var p))
+                    p.Add(item);
+                else
+                    tmp[(item.Item.PrimaryId, item.Item.Type)] = [item];
+            }
+
+            foreach (var list in tmp.Values)
+            {
+                list.Sort((i1, i2) =>
+                {
+                    // reversed
+                    var count = i2.Count.CompareTo(i1.Count);
+                    if (count != 0)
+                        return count;
+
+                    return string.Compare(i1.Item.Name, i2.Item.Name, StringComparison.Ordinal);
+                });
+            }
+
+            var sortedTmp = tmp.Values.OrderBy(s => s[0].Item.Name).ToArray();
+
+            var sortedTmpIdx = 0;
+            foreach (var (s, i) in _lastSelected.ChangedItems)
+            {
+                if (i is IdentifiedItem)
+                    continue;
+
+                if (!drawer.FilterChangedItem(s, i, LowerString.Empty))
+                    continue;
+
+                while (sortedTmpIdx < sortedTmp.Length
+                    && string.Compare(sortedTmp[sortedTmpIdx][0].Item.Name, s, StringComparison.Ordinal) <= 0)
+                    AddList(sortedTmp[sortedTmpIdx++]);
+
+                Data.Add(Container.Single(s, i));
+            }
+
+            for (; sortedTmpIdx < sortedTmp.Length; ++sortedTmpIdx)
+                AddList(sortedTmp[sortedTmpIdx]);
+            return;
+
+            void AddList(List<IdentifiedItem> list)
+            {
+                var mainItem = list[0];
+                if (list.Count == 1)
+                {
+                    Data.Add(Container.Single(mainItem.Item.Name, mainItem));
+                }
+                else
+                {
+                    var id       = ImUtf8.GetId($"{mainItem.Item.PrimaryId}{(int)mainItem.Item.Type}");
+                    var expanded = ImGui.GetStateStorage().GetBool(id, false);
+                    Data.Add(Container.Parent(mainItem.Item.Name, mainItem, id, list.Count - 1, expanded));
+                    AnyExpandable = true;
+                    if (!expanded)
+                        return;
+
+                    foreach (var item in list.Skip(1))
+                        Data.Add(Container.Indent(item.Item.Name, item));
+                }
+            }
+        }
+    }
+
     public ReadOnlySpan<byte> Label
         => "Changed Items"u8;
 
     public bool IsVisible
         => selector.Selected!.ChangedItems.Count > 0;
 
+    private ImGuiStoragePtr _stateStorage;
+
+    private Vector2 _buttonSize;
+
     public void DrawContent()
     {
+        if (cacheService.Cache(_cacheId, () => (new ChangedItemsCache(), "ModPanelChangedItemsCache")) is not { } cache)
+            return;
+
         drawer.DrawTypeFilter();
+
+        _stateStorage = ImGui.GetStateStorage();
+        cache.Update(selector.Selected, drawer, config.ChangedItemFilter);
         ImGui.Separator();
-        using var table = ImRaii.Table("##changedItems", 1, ImGuiTableFlags.RowBg | ImGuiTableFlags.ScrollY,
+        _buttonSize = new Vector2(ImGui.GetStyle().ItemSpacing.Y + ImGui.GetFrameHeight());
+        using var style = ImRaii.PushStyle(ImGuiStyleVar.CellPadding, Vector2.Zero)
+            .Push(ImGuiStyleVar.ItemSpacing,         Vector2.Zero)
+            .Push(ImGuiStyleVar.FramePadding,        Vector2.Zero)
+            .Push(ImGuiStyleVar.SelectableTextAlign, new Vector2(0.01f, 0.5f));
+
+        using var table = ImUtf8.Table("##changedItems"u8, cache.AnyExpandable ? 2 : 1, ImGuiTableFlags.RowBg | ImGuiTableFlags.ScrollY,
             new Vector2(ImGui.GetContentRegionAvail().X, -1));
         if (!table)
             return;
 
-        var zipList = ZipList.FromSortedList(selector.Selected!.ChangedItems);
+        if (cache.AnyExpandable)
-        var height  = ImGui.GetFrameHeightWithSpacing();
+        {
-        ImGui.TableNextColumn();
+            ImUtf8.TableSetupColumn("##exp"u8,  ImGuiTableColumnFlags.WidthFixed, _buttonSize.Y);
-        var skips     = ImGuiClip.GetNecessarySkips(height);
+            ImUtf8.TableSetupColumn("##text"u8, ImGuiTableColumnFlags.WidthStretch);
-        var remainder = ImGuiClip.FilteredClippedDraw(zipList, skips, CheckFilter, DrawChangedItem);
+            ImGuiClip.ClippedDraw(cache.Data, DrawContainerExpandable, _buttonSize.Y);
-        ImGuiClip.DrawEndDummy(remainder, height);
+        }
+        else
+        {
+            ImGuiClip.ClippedDraw(cache.Data, DrawContainer, ImGui.GetFrameHeightWithSpacing());
+        }
     }
 
-    private bool CheckFilter((string Name, IIdentifiedObjectData? Data) kvp)
+    private void DrawContainerExpandable(ChangedItemsCache.Container obj, int idx)
-        => drawer.FilterChangedItem(kvp.Name, kvp.Data, LowerString.Empty);
+    {
+        using var id = ImUtf8.PushId(idx);
+        ImGui.TableNextColumn();
+        if (obj.Expandable)
+        {
+            using var color = ImRaii.PushColor(ImGuiCol.Button, 0);
+            if (ImUtf8.IconButton(obj.Expanded ? FontAwesomeIcon.CaretDown : FontAwesomeIcon.CaretRight,
+                    obj.Expanded     ? "Hide the other items using the same model." :
+                    obj.Children > 1 ? $"Show {obj.Children} other items using the same model." :
+                                       "Show one other item using the same model.",
+                    _buttonSize))
+            {
+                _stateStorage.SetBool(obj.Id, !obj.Expanded);
+                if (cacheService.TryGetCache<ChangedItemsCache>(_cacheId, out var cache))
+                    cache.Reset();
+            }
+        }
+        else
+        {
+            ImGui.Dummy(_buttonSize);
+        }
 
-    private void DrawChangedItem((string Name, IIdentifiedObjectData? Data) kvp)
+        DrawBaseContainer(obj, idx);
+    }
+
+    private void DrawContainer(ChangedItemsCache.Container obj, int idx)
+    {
+        using var id = ImUtf8.PushId(idx);
+        DrawBaseContainer(obj, idx);
+    }
+
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private void DrawBaseContainer(in ChangedItemsCache.Container obj, int idx)
     {
         ImGui.TableNextColumn();
-        drawer.DrawCategoryIcon(kvp.Data);
+        using var indent = ImRaii.PushIndent(1, obj.Child);
-        ImGui.SameLine();
+        drawer.DrawCategoryIcon(obj.Icon, _buttonSize.Y);
-        drawer.DrawChangedItem(kvp.Name, kvp.Data);
+        ImGui.SameLine(0, 0);
-        ChangedItemDrawer.DrawModelData(kvp.Data);
+        var clicked = ImUtf8.Selectable(obj.Text.Span, false, ImGuiSelectableFlags.None, _buttonSize with { X = 0 });
+        drawer.ChangedItemHandling(obj.Data, clicked);
+        ChangedItemDrawer.DrawModelData(obj.ModelData.Span, _buttonSize.Y);
     }
 }

Penumbra/UI/Tabs/ChangedItemsTab.cs

@@ -3,6 +3,7 @@ using OtterGui;
 using OtterGui.Classes;
 using OtterGui.Raii;
 using OtterGui.Services;
+using OtterGui.Text;
 using OtterGui.Widgets;
 using Penumbra.Api.Enums;
 using Penumbra.Collections.Manager;
@@ -26,30 +27,36 @@ public class ChangedItemsTab(
 
     private LowerString _changedItemFilter    = LowerString.Empty;
     private LowerString _changedItemModFilter = LowerString.Empty;
+    private Vector2     _buttonSize;
 
     public void DrawContent()
     {
         collectionHeader.Draw(true);
         drawer.DrawTypeFilter();
         var       varWidth = DrawFilters();
-        using var child    = ImRaii.Child("##changedItemsChild", -Vector2.One);
+        using var child    = ImUtf8.Child("##changedItemsChild"u8, -Vector2.One);
         if (!child)
             return;
 
-        var height  = ImGui.GetFrameHeightWithSpacing() + 2 * ImGui.GetStyle().CellPadding.Y;
+        _buttonSize = new Vector2(ImGui.GetStyle().ItemSpacing.Y + ImGui.GetFrameHeight());
-        var       skips  = ImGuiClip.GetNecessarySkips(height);
+        using var style = ImRaii.PushStyle(ImGuiStyleVar.CellPadding, Vector2.Zero)
-        using var list   = ImRaii.Table("##changedItems", 3, ImGuiTableFlags.RowBg, -Vector2.One);
+            .Push(ImGuiStyleVar.ItemSpacing,         Vector2.Zero)
+            .Push(ImGuiStyleVar.FramePadding,        Vector2.Zero)
+            .Push(ImGuiStyleVar.SelectableTextAlign, new Vector2(0.01f, 0.5f));
+
+        var       skips = ImGuiClip.GetNecessarySkips(_buttonSize.Y);
+        using var list  = ImUtf8.Table("##changedItems"u8, 3, ImGuiTableFlags.RowBg, -Vector2.One);
         if (!list)
             return;
 
         const ImGuiTableColumnFlags flags = ImGuiTableColumnFlags.NoResize | ImGuiTableColumnFlags.WidthFixed;
-        ImGui.TableSetupColumn("items", flags, 450 * UiHelpers.Scale);
+        ImUtf8.TableSetupColumn("items"u8, flags, 450 * UiHelpers.Scale);
-        ImGui.TableSetupColumn("mods",  flags, varWidth - 130 * UiHelpers.Scale);
+        ImUtf8.TableSetupColumn("mods"u8,  flags, varWidth - 140 * UiHelpers.Scale);
-        ImGui.TableSetupColumn("id",    flags, 130 * UiHelpers.Scale);
+        ImUtf8.TableSetupColumn("id"u8,    flags, 140 * UiHelpers.Scale);
 
         var items = collectionManager.Active.Current.ChangedItems;
         var rest  = ImGuiClip.FilteredClippedDraw(items, skips, FilterChangedItem, DrawChangedItemColumn);
-        ImGuiClip.DrawEndDummy(rest, height);
+        ImGuiClip.DrawEndDummy(rest, _buttonSize.Y);
     }
 
     /// <summary> Draw a pair of filters and return the variable width of the flexible column. </summary>
@@ -67,22 +74,25 @@ public class ChangedItemsTab(
     }
 
     /// <summary> Apply the current filters. </summary>
-    private bool FilterChangedItem(KeyValuePair<string, (SingleArray<IMod>, IIdentifiedObjectData?)> item)
+    private bool FilterChangedItem(KeyValuePair<string, (SingleArray<IMod>, IIdentifiedObjectData)> item)
         => drawer.FilterChangedItem(item.Key, item.Value.Item2, _changedItemFilter)
          && (_changedItemModFilter.IsEmpty || item.Value.Item1.Any(m => m.Name.Contains(_changedItemModFilter)));
 
     /// <summary> Draw a full column for a changed item. </summary>
-    private void DrawChangedItemColumn(KeyValuePair<string, (SingleArray<IMod>, IIdentifiedObjectData?)> item)
+    private void DrawChangedItemColumn(KeyValuePair<string, (SingleArray<IMod>, IIdentifiedObjectData)> item)
     {
         ImGui.TableNextColumn();
-        drawer.DrawCategoryIcon(item.Value.Item2);
+        drawer.DrawCategoryIcon(item.Value.Item2, _buttonSize.Y);
-        ImGui.SameLine();
+        ImGui.SameLine(0, 0);
-        drawer.DrawChangedItem(item.Key, item.Value.Item2);
+        var name    = item.Value.Item2.ToName(item.Key);
+        var clicked = ImUtf8.Selectable(name, false, ImGuiSelectableFlags.None, _buttonSize with { X = 0 });
+        drawer.ChangedItemHandling(item.Value.Item2, clicked);
+
         ImGui.TableNextColumn();
         DrawModColumn(item.Value.Item1);
 
         ImGui.TableNextColumn();
-        ChangedItemDrawer.DrawModelData(item.Value.Item2);
+        ChangedItemDrawer.DrawModelData(item.Value.Item2, _buttonSize.Y);
     }
 
     private void DrawModColumn(SingleArray<IMod> mods)
@@ -90,19 +100,18 @@ public class ChangedItemsTab(
         if (mods.Count <= 0)
             return;
 
-        var       first = mods[0];
+        var first = mods[0];
-        using var style = ImRaii.PushStyle(ImGuiStyleVar.SelectableTextAlign, new Vector2(0, 0.5f));
+        if (ImUtf8.Selectable(first.Name.Text, false, ImGuiSelectableFlags.None, _buttonSize with { X = 0 })
-        if (ImGui.Selectable(first.Name, false, ImGuiSelectableFlags.None, new Vector2(0, ImGui.GetFrameHeight()))
          && ImGui.GetIO().KeyCtrl
          && first is Mod mod)
             communicator.SelectTab.Invoke(TabType.Mods, mod);
 
-        if (ImGui.IsItemHovered())
+        if (!ImGui.IsItemHovered())
-        {
+            return;
-            using var _ = ImRaii.Tooltip();
+
-            ImGui.TextUnformatted("Hold Control and click to jump to mod.\n");
+        using var _ = ImRaii.Tooltip();
-            if (mods.Count > 1)
+        ImUtf8.Text("Hold Control and click to jump to mod.\n"u8);
-                ImGui.TextUnformatted("Other mods affecting this item:\n" + string.Join("\n", mods.Skip(1).Select(m => m.Name)));
+        if (mods.Count > 1)
-        }
+            ImUtf8.Text("Other mods affecting this item:\n" + string.Join("\n", mods.Skip(1).Select(m => m.Name)));
     }
 }

Penumbra/UI/Tabs/Debug/DebugTab.cs

@@ -748,7 +748,7 @@ public class DebugTab : Window, ITab, IUiService
     }
 
     private          string                                     _changedItemPath = string.Empty;
-    private readonly Dictionary<string, IIdentifiedObjectData?> _changedItems    = [];
+    private readonly Dictionary<string, IIdentifiedObjectData> _changedItems    = [];
 
     private void DrawChangedItemTest()
     {

Penumbra/Util/IdentifierExtensions.cs

@@ -10,7 +10,7 @@ namespace Penumbra.Util;
 public static class IdentifierExtensions
 {
     public static void AddChangedItems(this ObjectIdentification identifier, IModDataContainer container,
-        IDictionary<string, IIdentifiedObjectData?> changedItems)
+        IDictionary<string, IIdentifiedObjectData> changedItems)
     {
         foreach (var gamePath in container.Files.Keys.Concat(container.FileSwaps.Keys))
             identifier.Identify(changedItems, gamePath.ToString());
@@ -19,7 +19,7 @@ public static class IdentifierExtensions
             manip.AddChangedItems(identifier, changedItems);
     }
 
-    public static void RemoveMachinistOffhands(this SortedList<string, IIdentifiedObjectData?> changedItems)
+    public static void RemoveMachinistOffhands(this SortedList<string, IIdentifiedObjectData> changedItems)
     {
         for (var i = 0; i < changedItems.Count; i++)
         {
@@ -31,7 +31,7 @@ public static class IdentifierExtensions
         }
     }
 
-    public static void RemoveMachinistOffhands(this SortedList<string, (SingleArray<IMod>, IIdentifiedObjectData?)> changedItems)
+    public static void RemoveMachinistOffhands(this SortedList<string, (SingleArray<IMod>, IIdentifiedObjectData)> changedItems)
     {
         for (var i = 0; i < changedItems.Count; i++)
         {