diff --git a/imgui.cpp b/imgui.cpp
index e3d2b65..6ca7697 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -1839,7 +1839,6 @@
     Appearing = false;
     BeginCount = 0;
     PopupId = 0;
-    NavLastIds[0] = NavLastIds[1] = 0;
     AutoFitFramesX = AutoFitFramesY = -1;
     AutoFitOnlyGrows = false;
     AutoFitChildAxises = 0x00;
@@ -1848,6 +1847,9 @@
     SetWindowPosAllowFlags = SetWindowSizeAllowFlags = SetWindowCollapsedAllowFlags = ImGuiCond_Always | ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing;
     SetWindowPosVal = SetWindowPosPivot = ImVec2(FLT_MAX, FLT_MAX);
 
+    NavLastIds[0] = NavLastIds[1] = 0;
+    NavRefRectRel[0] = NavRefRectRel[1] = ImRect();
+
     LastFrameActive = -1;
     ItemWidthDefault = 0.0f;
     FontWindowScale = 1.0f;
@@ -2223,7 +2225,7 @@
                 // Update window-relative bounding box of navigated item
                 if (g.NavId == *id)
                 {
-                    g.NavRefRectRel = nav_bb_rel;
+                    window->NavRefRectRel[window->DC.NavLayerCurrent] = nav_bb_rel;
                     g.NavIdIsAlive = true;
                     g.NavIdTabCounter = window->FocusIdxTabCounter;
                 }
@@ -2459,7 +2461,7 @@
 {
     ImGuiContext& g = *GImGui;
     SetNavId(id, nav_layer);
-    g.NavRefRectRel = rect_rel;
+    g.NavWindow->NavRefRectRel[nav_layer] = rect_rel;
     g.NavMousePosDirty = true;
     g.NavDisableHighlight = false;
     g.NavDisableMouseHover = true;
@@ -2487,11 +2489,13 @@
 static ImVec2 NavCalcPreferredMousePos()
 {
     ImGuiContext& g = *GImGui;
-    if (!g.NavWindow)
+    ImGuiWindow* window = g.NavWindow;
+    if (!window)
         return g.IO.MousePos;
-    ImVec2 p = g.NavWindow->Pos + ImVec2(g.NavRefRectRel.Min.x + ImMin(g.Style.FramePadding.x*4, g.NavRefRectRel.GetWidth()), g.NavRefRectRel.Max.y - ImMin(g.Style.FramePadding.y, g.NavRefRectRel.GetHeight()));
-    ImRect r = GetVisibleRect();
-    return ImFloor(ImClamp(p, r.Min, r.Max));   // ImFloor() is important because non-integer mouse position application in backend might be lossy and result in undesirable non-zero delta.
+    const ImRect& ref_rect_rel = window->NavRefRectRel[g.NavLayer];
+    ImVec2 pos = g.NavWindow->Pos + ImVec2(ref_rect_rel.Min.x + ImMin(g.Style.FramePadding.x*4, ref_rect_rel.GetWidth()), ref_rect_rel.Max.y - ImMin(g.Style.FramePadding.y, ref_rect_rel.GetHeight()));
+    ImRect visible_rect = GetVisibleRect();
+    return ImFloor(ImClamp(pos, visible_rect.Min, visible_rect.Max));   // ImFloor() is important because non-integer mouse position application in backend might be lossy and result in undesirable non-zero delta.
 }
 
 static int FindWindowIndex(ImGuiWindow* window) // FIXME-OPT O(N)
@@ -2580,7 +2584,7 @@
         // Apply result from previous navigation init request (typically select the first item, unless SetItemDefaultFocus() has been called)
         IM_ASSERT(g.NavWindow);
         SetNavId(g.NavInitDefaultResultId, g.NavLayer);
-        g.NavRefRectRel = g.NavInitDefaultResultRectRel;
+        g.NavWindow->NavRefRectRel[g.NavLayer] = g.NavInitDefaultResultRectRel;
         if (g.NavDisableMouseHover)
             g.NavMousePosDirty = true;
     }
@@ -2834,21 +2838,22 @@
     {
         // When we have manually scrolled and NavId is out of bounds, we clamp its bounding box (used for search) to the visible area to restart navigation within visible items
         ImRect window_rect_rel(g.NavWindow->InnerRect.Min - g.NavWindow->Pos - ImVec2(1,1), g.NavWindow->InnerRect.Max - g.NavWindow->Pos + ImVec2(1,1));
-        if (!window_rect_rel.Contains(g.NavRefRectRel))
+        if (!window_rect_rel.Contains(g.NavWindow->NavRefRectRel[g.NavLayer]))
         {
             float pad = g.NavWindow->CalcFontSize() * 0.5f;
             window_rect_rel.Expand(ImVec2(-ImMin(window_rect_rel.GetWidth(), pad), -ImMin(window_rect_rel.GetHeight(), pad))); // Terrible approximation for the intend of starting navigation from first fully visible item
-            g.NavRefRectRel.ClipWith(window_rect_rel);
+            g.NavWindow->NavRefRectRel[g.NavLayer].ClipWith(window_rect_rel);
             g.NavId = 0;
         }
         g.NavMoveFromClampedRefRect = false;
     }
 
     // For scoring we use a single segment on the left side our current item bounding box (not touching the edge to avoid box overlap with zero-spaced items)
-    g.NavScoringRectScreen = g.NavWindow ? ImRect(g.NavWindow->Pos + g.NavRefRectRel.Min, g.NavWindow->Pos + g.NavRefRectRel.Max) : ImRect();
+    g.NavScoringRectScreen = g.NavWindow ? ImRect(g.NavWindow->Pos + g.NavWindow->NavRefRectRel[g.NavLayer].Min, g.NavWindow->Pos + g.NavWindow->NavRefRectRel[g.NavLayer].Max) : ImRect();
     g.NavScoringRectScreen.Min.x = ImMin(g.NavScoringRectScreen.Min.x + 1.0f, g.NavScoringRectScreen.Max.x);
     g.NavScoringRectScreen.Max.x = g.NavScoringRectScreen.Min.x;
     //g.OverlayDrawList.AddRect(g.NavScoringRectScreen.Min, g.NavScoringRectScreen.Max, IM_COL32(255,200,0,255)); // [DEBUG]
+    //if (g.NavWindow) for (int layer = 0; layer < 2; layer++) g.OverlayDrawList.AddRect(g.NavWindow->Pos + g.NavWindow->NavRefRectRel[layer].Min, g.NavWindow->Pos + g.NavWindow->NavRefRectRel[layer].Max, IM_COL32(255,200,0,255)); // [DEBUG]
 }
 
 void ImGui::NewFrame()
@@ -5509,7 +5514,7 @@
         g.NavLayer = 0;
         if (window && g.NavDisableMouseHover)
             g.NavMousePosDirty = true;
-        g.NavRefRectRel.Min = g.NavRefRectRel.Max = window ? (window->DC.CursorStartPos - window->Pos) : ImVec2(0,0);
+        window->NavRefRectRel[0].Min = window->NavRefRectRel[1].Max = window ? (window->DC.CursorStartPos - window->Pos) : ImVec2(0,0);
         g.NavWindow = window;
     }
 
@@ -11622,6 +11627,7 @@
                 ImGui::BulletText("Scroll: (%.2f,%.2f)", window->Scroll.x, window->Scroll.y);
                 ImGui::BulletText("Active: %d, Accessed: %d", window->Active, window->Accessed);
                 ImGui::BulletText("NavLastIds: 0x%08X,0x%08X, NavLayerActiveMask: %X", window->NavLastIds[0], window->NavLastIds[1], window->DC.NavLayerActiveMask);
+                ImGui::BulletText("NavRefRectRel[0]: (%.1f,%.1f)(%.1f,%.1f)", window->NavRefRectRel[0].Min.x, window->NavRefRectRel[0].Min.y, window->NavRefRectRel[0].Max.x, window->NavRefRectRel[0].Max.y);
                 if (window->RootWindow != window) NodeWindow(window->RootWindow, "RootWindow");
                 if (window->DC.ChildWindows.Size > 0) NodeWindows(window->DC.ChildWindows, "ChildWindows");
                 ImGui::BulletText("Storage: %d bytes", window->StateStorage.Data.Size * (int)sizeof(ImGuiStorage::Pair));
@@ -11655,7 +11661,6 @@
             ImGui::Text("ActiveId: 0x%08X/0x%08X, ActiveIdSource: %s", g.ActiveId, g.ActiveIdPreviousFrame, input_source_names[g.ActiveIdSource]);
             ImGui::Text("ActiveIdWindow: '%s'", g.ActiveIdWindow ? g.ActiveIdWindow->Name : "NULL");
             ImGui::Text("NavWindow: '%s', NavId: 0x%08X, NavLayer: %d", g.NavWindow ? g.NavWindow->Name : "NULL", g.NavId, g.NavLayer);
-            ImGui::Text("NavRefRectRel: (%.1f,%.1f)(%.1f,%.1f)", g.NavRefRectRel.Min.x, g.NavRefRectRel.Min.y, g.NavRefRectRel.Max.x, g.NavRefRectRel.Max.y);
             ImGui::Text("NavUsable: %d, NavActive: %d", g.IO.NavUsable, g.IO.NavActive);
             ImGui::Text("NavActivateId: 0x%08X, NavInputId: 0x%08X", g.NavActivateId, g.NavInputId);
             ImGui::Text("NavDisableHighlight: %d, NavDisableMouseHover: %d", g.NavDisableHighlight, g.NavDisableMouseHover);

diff --git a/imgui.cpp b/imgui.cpp
index e3d2b65..6ca7697 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -1839,7 +1839,6 @@
     Appearing = false;
     BeginCount = 0;
     PopupId = 0;
-    NavLastIds[0] = NavLastIds[1] = 0;
     AutoFitFramesX = AutoFitFramesY = -1;
     AutoFitOnlyGrows = false;
     AutoFitChildAxises = 0x00;
@@ -1848,6 +1847,9 @@
     SetWindowPosAllowFlags = SetWindowSizeAllowFlags = SetWindowCollapsedAllowFlags = ImGuiCond_Always | ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing;
     SetWindowPosVal = SetWindowPosPivot = ImVec2(FLT_MAX, FLT_MAX);
 
+    NavLastIds[0] = NavLastIds[1] = 0;
+    NavRefRectRel[0] = NavRefRectRel[1] = ImRect();
+
     LastFrameActive = -1;
     ItemWidthDefault = 0.0f;
     FontWindowScale = 1.0f;
@@ -2223,7 +2225,7 @@
                 // Update window-relative bounding box of navigated item
                 if (g.NavId == *id)
                 {
-                    g.NavRefRectRel = nav_bb_rel;
+                    window->NavRefRectRel[window->DC.NavLayerCurrent] = nav_bb_rel;
                     g.NavIdIsAlive = true;
                     g.NavIdTabCounter = window->FocusIdxTabCounter;
                 }
@@ -2459,7 +2461,7 @@
 {
     ImGuiContext& g = *GImGui;
     SetNavId(id, nav_layer);
-    g.NavRefRectRel = rect_rel;
+    g.NavWindow->NavRefRectRel[nav_layer] = rect_rel;
     g.NavMousePosDirty = true;
     g.NavDisableHighlight = false;
     g.NavDisableMouseHover = true;
@@ -2487,11 +2489,13 @@
 static ImVec2 NavCalcPreferredMousePos()
 {
     ImGuiContext& g = *GImGui;
-    if (!g.NavWindow)
+    ImGuiWindow* window = g.NavWindow;
+    if (!window)
         return g.IO.MousePos;
-    ImVec2 p = g.NavWindow->Pos + ImVec2(g.NavRefRectRel.Min.x + ImMin(g.Style.FramePadding.x*4, g.NavRefRectRel.GetWidth()), g.NavRefRectRel.Max.y - ImMin(g.Style.FramePadding.y, g.NavRefRectRel.GetHeight()));
-    ImRect r = GetVisibleRect();
-    return ImFloor(ImClamp(p, r.Min, r.Max));   // ImFloor() is important because non-integer mouse position application in backend might be lossy and result in undesirable non-zero delta.
+    const ImRect& ref_rect_rel = window->NavRefRectRel[g.NavLayer];
+    ImVec2 pos = g.NavWindow->Pos + ImVec2(ref_rect_rel.Min.x + ImMin(g.Style.FramePadding.x*4, ref_rect_rel.GetWidth()), ref_rect_rel.Max.y - ImMin(g.Style.FramePadding.y, ref_rect_rel.GetHeight()));
+    ImRect visible_rect = GetVisibleRect();
+    return ImFloor(ImClamp(pos, visible_rect.Min, visible_rect.Max));   // ImFloor() is important because non-integer mouse position application in backend might be lossy and result in undesirable non-zero delta.
 }
 
 static int FindWindowIndex(ImGuiWindow* window) // FIXME-OPT O(N)
@@ -2580,7 +2584,7 @@
         // Apply result from previous navigation init request (typically select the first item, unless SetItemDefaultFocus() has been called)
         IM_ASSERT(g.NavWindow);
         SetNavId(g.NavInitDefaultResultId, g.NavLayer);
-        g.NavRefRectRel = g.NavInitDefaultResultRectRel;
+        g.NavWindow->NavRefRectRel[g.NavLayer] = g.NavInitDefaultResultRectRel;
         if (g.NavDisableMouseHover)
             g.NavMousePosDirty = true;
     }
@@ -2834,21 +2838,22 @@
     {
         // When we have manually scrolled and NavId is out of bounds, we clamp its bounding box (used for search) to the visible area to restart navigation within visible items
         ImRect window_rect_rel(g.NavWindow->InnerRect.Min - g.NavWindow->Pos - ImVec2(1,1), g.NavWindow->InnerRect.Max - g.NavWindow->Pos + ImVec2(1,1));
-        if (!window_rect_rel.Contains(g.NavRefRectRel))
+        if (!window_rect_rel.Contains(g.NavWindow->NavRefRectRel[g.NavLayer]))
         {
             float pad = g.NavWindow->CalcFontSize() * 0.5f;
             window_rect_rel.Expand(ImVec2(-ImMin(window_rect_rel.GetWidth(), pad), -ImMin(window_rect_rel.GetHeight(), pad))); // Terrible approximation for the intend of starting navigation from first fully visible item
-            g.NavRefRectRel.ClipWith(window_rect_rel);
+            g.NavWindow->NavRefRectRel[g.NavLayer].ClipWith(window_rect_rel);
             g.NavId = 0;
         }
         g.NavMoveFromClampedRefRect = false;
     }
 
     // For scoring we use a single segment on the left side our current item bounding box (not touching the edge to avoid box overlap with zero-spaced items)
-    g.NavScoringRectScreen = g.NavWindow ? ImRect(g.NavWindow->Pos + g.NavRefRectRel.Min, g.NavWindow->Pos + g.NavRefRectRel.Max) : ImRect();
+    g.NavScoringRectScreen = g.NavWindow ? ImRect(g.NavWindow->Pos + g.NavWindow->NavRefRectRel[g.NavLayer].Min, g.NavWindow->Pos + g.NavWindow->NavRefRectRel[g.NavLayer].Max) : ImRect();
     g.NavScoringRectScreen.Min.x = ImMin(g.NavScoringRectScreen.Min.x + 1.0f, g.NavScoringRectScreen.Max.x);
     g.NavScoringRectScreen.Max.x = g.NavScoringRectScreen.Min.x;
     //g.OverlayDrawList.AddRect(g.NavScoringRectScreen.Min, g.NavScoringRectScreen.Max, IM_COL32(255,200,0,255)); // [DEBUG]
+    //if (g.NavWindow) for (int layer = 0; layer < 2; layer++) g.OverlayDrawList.AddRect(g.NavWindow->Pos + g.NavWindow->NavRefRectRel[layer].Min, g.NavWindow->Pos + g.NavWindow->NavRefRectRel[layer].Max, IM_COL32(255,200,0,255)); // [DEBUG]
 }
 
 void ImGui::NewFrame()
@@ -5509,7 +5514,7 @@
         g.NavLayer = 0;
         if (window && g.NavDisableMouseHover)
             g.NavMousePosDirty = true;
-        g.NavRefRectRel.Min = g.NavRefRectRel.Max = window ? (window->DC.CursorStartPos - window->Pos) : ImVec2(0,0);
+        window->NavRefRectRel[0].Min = window->NavRefRectRel[1].Max = window ? (window->DC.CursorStartPos - window->Pos) : ImVec2(0,0);
         g.NavWindow = window;
     }
 
@@ -11622,6 +11627,7 @@
                 ImGui::BulletText("Scroll: (%.2f,%.2f)", window->Scroll.x, window->Scroll.y);
                 ImGui::BulletText("Active: %d, Accessed: %d", window->Active, window->Accessed);
                 ImGui::BulletText("NavLastIds: 0x%08X,0x%08X, NavLayerActiveMask: %X", window->NavLastIds[0], window->NavLastIds[1], window->DC.NavLayerActiveMask);
+                ImGui::BulletText("NavRefRectRel[0]: (%.1f,%.1f)(%.1f,%.1f)", window->NavRefRectRel[0].Min.x, window->NavRefRectRel[0].Min.y, window->NavRefRectRel[0].Max.x, window->NavRefRectRel[0].Max.y);
                 if (window->RootWindow != window) NodeWindow(window->RootWindow, "RootWindow");
                 if (window->DC.ChildWindows.Size > 0) NodeWindows(window->DC.ChildWindows, "ChildWindows");
                 ImGui::BulletText("Storage: %d bytes", window->StateStorage.Data.Size * (int)sizeof(ImGuiStorage::Pair));
@@ -11655,7 +11661,6 @@
             ImGui::Text("ActiveId: 0x%08X/0x%08X, ActiveIdSource: %s", g.ActiveId, g.ActiveIdPreviousFrame, input_source_names[g.ActiveIdSource]);
             ImGui::Text("ActiveIdWindow: '%s'", g.ActiveIdWindow ? g.ActiveIdWindow->Name : "NULL");
             ImGui::Text("NavWindow: '%s', NavId: 0x%08X, NavLayer: %d", g.NavWindow ? g.NavWindow->Name : "NULL", g.NavId, g.NavLayer);
-            ImGui::Text("NavRefRectRel: (%.1f,%.1f)(%.1f,%.1f)", g.NavRefRectRel.Min.x, g.NavRefRectRel.Min.y, g.NavRefRectRel.Max.x, g.NavRefRectRel.Max.y);
             ImGui::Text("NavUsable: %d, NavActive: %d", g.IO.NavUsable, g.IO.NavActive);
             ImGui::Text("NavActivateId: 0x%08X, NavInputId: 0x%08X", g.NavActivateId, g.NavInputId);
             ImGui::Text("NavDisableHighlight: %d, NavDisableMouseHover: %d", g.NavDisableHighlight, g.NavDisableMouseHover);
diff --git a/imgui_internal.h b/imgui_internal.h
index f87bd68..44c7973 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -459,7 +459,7 @@
     ImGuiID                 NavId;                              // Nav/focused item for navigation
     ImGuiID                 NavActivateId, NavInputId;          // ~~ IsKeyPressedMap(ImGuiKey_NavActive) ? NavId : 0, etc. (to make widget code terser)
     ImGuiID                 NavTabbedId;                        // 
-    ImRect                  NavRefRectRel, NavScoringRectScreen;// Reference rectangle, in window space. Modified rectangle for directional navigation scoring, in screen space.
+    ImRect                  NavScoringRectScreen;               // Rectangle used for scoring, in screen space. Based of window->DC.NavRefRectRel[], modified for directional navigation scoring.
     ImGuiWindow*            NavWindowingTarget;
     float                   NavWindowingDisplayAlpha;
     bool                    NavWindowingToggleLayer;
@@ -571,7 +571,7 @@
 
         NavWindow = NULL;
         NavId = NavActivateId = NavInputId = NavTabbedId = 0;
-        NavRefRectRel = NavScoringRectScreen = ImRect();
+        NavScoringRectScreen = ImRect();
         NavWindowingTarget = NULL;
         NavWindowingDisplayAlpha = 0.0f;
         NavWindowingToggleLayer = false;
@@ -775,7 +775,8 @@
     ImVec2                  SetWindowPosVal;                    // store window position when using a non-zero Pivot (position set needs to be processed when we know the window size)
     ImVec2                  SetWindowPosPivot;                  // store window pivot for positioning. ImVec2(0,0) when positioning from top-left corner; ImVec2(0.5f,0.5f) for centering; ImVec2(1,1) for bottom right.
 
-    ImGuiID                 NavLastIds[2];                       // Last known NavId for this window, per layer (0/1)
+    ImGuiID                 NavLastIds[2];                      // Last known NavId for this window, per layer (0/1)
+    ImRect                  NavRefRectRel[2];                   // Reference rectangle, in window space
 
     ImGuiDrawContext        DC;                                 // Temporary per-window data, reset at the beginning of the frame
     ImVector<ImGuiID>       IDStack;                            // ID stack. ID are hashes seeded with the value at the top of the stack