Update ImGUI to 1.82 + docking.

1 files changed, 378 insertions, 285 deletions

diff --git a/imgui/imgui.cpp b/imgui/imgui.cpp
index 1d5c88a1..1bf605ad 100644
--- a/imgui/imgui.cpp
+++ b/imgui/imgui.cpp
@@ -1,4 +1,4 @@
-// dear imgui, v1.81
+// dear imgui, v1.82
 // (main code and documentation)
 
 // Help:
@@ -15,6 +15,7 @@
 // - Glossary              https://github.com/ocornut/imgui/wiki/Glossary
 // - Wiki                  https://github.com/ocornut/imgui/wiki
 // - Issues & support      https://github.com/ocornut/imgui/issues
+// - Discussions           https://github.com/ocornut/imgui/discussions
 
 // Developed by Omar Cornut and every direct or indirect contributors to the GitHub.
 // See LICENSE.txt for copyright and licensing details (standard MIT License).
@@ -376,15 +377,34 @@ CODE
  When you are not sure about a old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
- (Docking/Viewport Branch)
- - 2020/XX/XX (1.XX) - when multi-viewports are enabled, all positions will be in your natural OS coordinates space. It means that:
+(Docking/Viewport Branch)
+ - 2021/XX/XX (1.XX) - when multi-viewports are enabled, all positions will be in your natural OS coordinates space. It means that:
                         - reference to hard-coded positions such as in SetNextWindowPos(ImVec2(0,0)) are probably not what you want anymore.
                           you may use GetMainViewport()->Pos to offset hard-coded positions, e.g. SetNextWindowPos(GetMainViewport()->Pos)
                         - likewise io.MousePos and GetMousePos() will use OS coordinates.
                           If you query mouse positions to interact with non-imgui coordinates you will need to offset them, e.g. subtract GetWindowViewport()->Pos.
- - 2020/XX/XX (1.XX) - Moved IME support functions from io.ImeSetInputScreenPosFn, io.ImeWindowHandle to the PlatformIO api.
-
-
+ - 2021/XX/XX (1.XX) - Moved IME support functions from io.ImeSetInputScreenPosFn, io.ImeWindowHandle to the PlatformIO api.
+
+
+ - 2021/03/12 (1.82) - upgraded ImDrawList::AddRect(), AddRectFilled(), PathRect() to use ImDrawFlags instead of ImDrawCornersFlags.
+                        - ImDrawCornerFlags_TopLeft  -> use ImDrawFlags_RoundCornersTopLeft
+                        - ImDrawCornerFlags_BotRight -> use ImDrawFlags_RoundCornersBottomRight
+                        - ImDrawCornerFlags_None     -> use ImDrawFlags_RoundCornersNone etc.
+                       flags now sanely defaults to 0 instead of 0x0F, consistent with all other flags in the API.
+                       breaking: the default with rounding > 0.0f is now "round all corners" vs old implicit "round no corners":
+                        - rounding == 0.0f + flags == 0 --> meant no rounding  --> unchanged (common use)
+                        - rounding  > 0.0f + flags != 0 --> meant rounding     --> unchanged (common use)
+                        - rounding == 0.0f + flags != 0 --> meant no rounding  --> unchanged (unlikely use)
+                        - rounding  > 0.0f + flags == 0 --> meant no rounding  --> BREAKING (unlikely use): will now round all corners --> use ImDrawFlags_RoundCornersNone or rounding == 0.0f.
+                       this ONLY matters for hard coded use of 0 + rounding > 0.0f. Use of named ImDrawFlags_RoundCornersNone (new) or ImDrawCornerFlags_None (old) are ok.
+                       the old ImDrawCornersFlags used awkward default values of ~0 or 0xF (4 lower bits set) to signify "round all corners" and we sometimes encouraged using them as shortcuts.
+                       legacy path still support use of hard coded ~0 or any value from 0x1 or 0xF. They will behave the same with legacy paths enabled (will assert otherwise).
+ - 2021/03/11 (1.82) - removed redirecting functions/enums names that were marked obsolete in 1.66 (September 2018):
+                        - ImGui::SetScrollHere()              -> use ImGui::SetScrollHereY()
+ - 2021/03/11 (1.82) - clarified that ImDrawList::PathArcTo(), ImDrawList::PathArcToFast() won't render with radius < 0.0f. Previously it sorts of accidentally worked but would generally lead to counter-clockwise paths and have an effect on anti-aliasing.
+ - 2021/03/10 (1.82) - upgraded ImDrawList::AddPolyline() and PathStroke() "bool closed" parameter to "ImDrawFlags flags". The matching ImDrawFlags_Closed value is guaranteed to always stay == 1 in the future.
+ - 2021/02/22 (1.82) - win32+mingw: Re-enabled IME functions by default even under MinGW. In July 2016, issue #738 had me incorrectly disable those default functions for MinGW. MinGW users should: either link with -limm32, either set their imconfig file  with '#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS'.
+ - 2021/02/17 (1.82) - renamed rarely used style.CircleSegmentMaxError (old default = 1.60f) to style.CircleTessellationMaxError (new default = 0.30f) as the meaning of the value changed.
  - 2021/02/03 (1.81) - renamed ListBoxHeader(const char* label, ImVec2 size) to BeginListBox(). Kept inline redirection function (will obsolete).
                      - removed ListBoxHeader(const char* label, int items_count, int height_in_items = -1) in favor of specifying size. Kept inline redirection function (will obsolete).
                      - renamed ListBoxFooter() to EndListBox(). Kept inline redirection function (will obsolete).
@@ -896,6 +916,7 @@ static void             NavProcessItem(ImGuiWindow* window, const ImRect& nav_bb
 static ImVec2           NavCalcPreferredRefPos();
 static void             NavSaveLastChildNavWindowIntoParent(ImGuiWindow* nav_window);
 static ImGuiWindow*     NavRestoreLastChildNavWindow(ImGuiWindow* window);
+static void             NavRestoreLayer(ImGuiNavLayer layer);
 static int              FindWindowFocusIndex(ImGuiWindow* window);
 
 // Error Checking
@@ -934,27 +955,33 @@ static void             UpdateViewportPlatformMonitor(ImGuiViewportP* viewport);
 // [SECTION] CONTEXT AND MEMORY ALLOCATORS
 //-----------------------------------------------------------------------------
 
+// DLL users:
+// - Heaps and globals are not shared across DLL boundaries!
+// - You will need to call SetCurrentContext() + SetAllocatorFunctions() for each static/DLL boundary you are calling from.
+// - Same apply for hot-reloading mechanisms that are reliant on reloading DLL (note that many hot-reloading mechanism works without DLL).
+// - Using Dear ImGui via a shared library is not recommended, because of function call overhead and because we don't guarantee backward nor forward ABI compatibility.
+// - Confused? In a debugger: add GImGui to your watch window and notice how its value changes depending on your current location (which DLL boundary you are in).
+
 // Current context pointer. Implicitly used by all Dear ImGui functions. Always assumed to be != NULL.
-// ImGui::CreateContext() will automatically set this pointer if it is NULL. Change to a different context by calling ImGui::SetCurrentContext().
-// 1) Important: globals are not shared across DLL boundaries! If you use DLLs or any form of hot-reloading: you will need to call
-//    SetCurrentContext() (with the pointer you got from CreateContext) from each unique static/DLL boundary, and after each hot-reloading.
-//    In your debugger, add GImGui to your watch window and notice how its value changes depending on which location you are currently stepping into.
-// 2) Important: Dear ImGui functions are not thread-safe because of this pointer.
-//    If you want thread-safety to allow N threads to access N different contexts, you can:
-//    - Change this variable to use thread local storage so each thread can refer to a different context, in imconfig.h:
-//          struct ImGuiContext;
-//          extern thread_local ImGuiContext* MyImGuiTLS;
-//          #define GImGui MyImGuiTLS
-//      And then define MyImGuiTLS in one of your cpp file. Note that thread_local is a C++11 keyword, earlier C++ uses compiler-specific keyword.
-//    - Future development aim to make this context pointer explicit to all calls. Also read https://github.com/ocornut/imgui/issues/586
-//    - If you need a finite number of contexts, you may compile and use multiple instances of the ImGui code from different namespace.
+// - ImGui::CreateContext() will automatically set this pointer if it is NULL.
+//   Change to a different context by calling ImGui::SetCurrentContext().
+// - Important: Dear ImGui functions are not thread-safe because of this pointer.
+//   If you want thread-safety to allow N threads to access N different contexts:
+//   - Change this variable to use thread local storage so each thread can refer to a different context, in your imconfig.h:
+//         struct ImGuiContext;
+//         extern thread_local ImGuiContext* MyImGuiTLS;
+//         #define GImGui MyImGuiTLS
+//     And then define MyImGuiTLS in one of your cpp file. Note that thread_local is a C++11 keyword, earlier C++ uses compiler-specific keyword.
+//   - Future development aim to make this context pointer explicit to all calls. Also read https://github.com/ocornut/imgui/issues/586
+//   - If you need a finite number of contexts, you may compile and use multiple instances of the ImGui code from different namespace.
+// - DLL users: read comments above.
 #ifndef GImGui
 ImGuiContext*   GImGui = NULL;
 #endif
 
 // Memory Allocator functions. Use SetAllocatorFunctions() to change them.
-// If you use DLL hotreloading you might need to call SetAllocatorFunctions() after reloading code from this file.
-// Otherwise, you probably don't want to modify them mid-program, and if you use global/static e.g. ImVector<> instances you may need to keep them accessible during program destruction.
+// - You probably don't want to modify those mid-program, and if you use global/static e.g. ImVector<> instances you may need to keep them accessible during program destruction.
+// - DLL users: read comments above.
 #ifndef IMGUI_DISABLE_DEFAULT_ALLOCATORS
 static void*   MallocWrapper(size_t size, void* user_data)    { IM_UNUSED(user_data); return malloc(size); }
 static void    FreeWrapper(void* ptr, void* user_data)        { IM_UNUSED(user_data); free(ptr); }
@@ -962,10 +989,9 @@ static void    FreeWrapper(void* ptr, void* user_data)        { IM_UNUSED(user_d
 static void*   MallocWrapper(size_t size, void* user_data)    { IM_UNUSED(user_data); IM_UNUSED(size); IM_ASSERT(0); return NULL; }
 static void    FreeWrapper(void* ptr, void* user_data)        { IM_UNUSED(user_data); IM_UNUSED(ptr); IM_ASSERT(0); }
 #endif
-
-static void*  (*GImAllocatorAllocFunc)(size_t size, void* user_data) = MallocWrapper;
-static void   (*GImAllocatorFreeFunc)(void* ptr, void* user_data) = FreeWrapper;
-static void*    GImAllocatorUserData = NULL;
+static ImGuiMemAllocFunc    GImAllocatorAllocFunc = MallocWrapper;
+static ImGuiMemFreeFunc     GImAllocatorFreeFunc = FreeWrapper;
+static void*                GImAllocatorUserData = NULL;
 
 //-----------------------------------------------------------------------------
 // [SECTION] USER FACING STRUCTURES (ImGuiStyle, ImGuiIO)
@@ -1011,7 +1037,7 @@ ImGuiStyle::ImGuiStyle()
     AntiAliasedLinesUseTex  = true;             // Enable anti-aliased lines/borders using textures where possible. Require backend to render with bilinear filtering.
     AntiAliasedFill         = true;             // Enable anti-aliased filled shapes (rounded rectangles, circles, etc.).
     CurveTessellationTol    = 1.25f;            // Tessellation tolerance when using PathBezierCurveTo() without a specific number of segments. Decrease for highly tessellated curves (higher quality, more polygons), increase to reduce quality.
-    CircleSegmentMaxError   = 1.60f;            // Maximum error (in pixels) allowed when using AddCircle()/AddCircleFilled() or drawing rounded corner rectangles with no explicit segment count specified. Decrease for higher quality but more geometry.
+    CircleTessellationMaxError = 0.30f;         // Maximum error (in pixels) allowed when using AddCircle()/AddCircleFilled() or drawing rounded corner rectangles with no explicit segment count specified. Decrease for higher quality but more geometry.
 
     // Default theme
     ImGui::StyleColorsDark(this);
@@ -2842,8 +2868,8 @@ void ImGui::RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border,
     const float border_size = g.Style.FrameBorderSize;
     if (border && border_size > 0.0f)
     {
-        window->DrawList->AddRect(p_min + ImVec2(1, 1), p_max + ImVec2(1, 1), GetColorU32(ImGuiCol_BorderShadow), rounding, ImDrawCornerFlags_All, border_size);
-        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+        window->DrawList->AddRect(p_min + ImVec2(1, 1), p_max + ImVec2(1, 1), GetColorU32(ImGuiCol_BorderShadow), rounding, 0, border_size);
+        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, 0, border_size);
     }
 }
 
@@ -2854,8 +2880,8 @@ void ImGui::RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding)
     const float border_size = g.Style.FrameBorderSize;
     if (border_size > 0.0f)
     {
-        window->DrawList->AddRect(p_min + ImVec2(1, 1), p_max + ImVec2(1, 1), GetColorU32(ImGuiCol_BorderShadow), rounding, ImDrawCornerFlags_All, border_size);
-        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+        window->DrawList->AddRect(p_min + ImVec2(1, 1), p_max + ImVec2(1, 1), GetColorU32(ImGuiCol_BorderShadow), rounding, 0, border_size);
+        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, 0, border_size);
     }
 }
 
@@ -2881,13 +2907,13 @@ void ImGui::RenderNavHighlight(const ImRect& bb, ImGuiID id, ImGuiNavHighlightFl
         bool fully_visible = window->ClipRect.Contains(display_rect);
         if (!fully_visible)
             window->DrawList->PushClipRect(display_rect.Min, display_rect.Max);
-        window->DrawList->AddRect(display_rect.Min + ImVec2(THICKNESS * 0.5f, THICKNESS * 0.5f), display_rect.Max - ImVec2(THICKNESS * 0.5f, THICKNESS * 0.5f), GetColorU32(ImGuiCol_NavHighlight), rounding, ImDrawCornerFlags_All, THICKNESS);
+        window->DrawList->AddRect(display_rect.Min + ImVec2(THICKNESS * 0.5f, THICKNESS * 0.5f), display_rect.Max - ImVec2(THICKNESS * 0.5f, THICKNESS * 0.5f), GetColorU32(ImGuiCol_NavHighlight), rounding, 0, THICKNESS);
         if (!fully_visible)
             window->DrawList->PopClipRect();
     }
     if (flags & ImGuiNavHighlightFlags_TypeThin)
     {
-        window->DrawList->AddRect(display_rect.Min, display_rect.Max, GetColorU32(ImGuiCol_NavHighlight), rounding, ~0, 1.0f);
+        window->DrawList->AddRect(display_rect.Min, display_rect.Max, GetColorU32(ImGuiCol_NavHighlight), rounding, 0, 1.0f);
     }
 }
 
@@ -3062,6 +3088,7 @@ void ImGui::SetActiveID(ImGuiID id, ImGuiWindow* window)
         g.ActiveIdTimer = 0.0f;
         g.ActiveIdHasBeenPressedBefore = false;
         g.ActiveIdHasBeenEditedBefore = false;
+        g.ActiveIdMouseButton = -1;
         if (id != 0)
         {
             g.LastActiveId = id;
@@ -3136,8 +3163,8 @@ static inline bool IsWindowContentHoverable(ImGuiWindow* window, ImGuiHoveredFla
     // FIXME-OPT: This could be cached/stored within the window.
     ImGuiContext& g = *GImGui;
     if (g.NavWindow)
-        if (ImGuiWindow* focused_root_window = g.NavWindow->RootWindow)
-            if (focused_root_window->WasActive && focused_root_window != window->RootWindow)
+        if (ImGuiWindow* focused_root_window = g.NavWindow->RootWindowDockTree)
+            if (focused_root_window->WasActive && focused_root_window != window->RootWindowDockTree)
             {
                 // For the purpose of those flags we differentiate "standard popup" from "modal popup"
                 // NB: The order of those two tests is important because Modal windows are also Popups.
@@ -3149,7 +3176,7 @@ static inline bool IsWindowContentHoverable(ImGuiWindow* window, ImGuiHoveredFla
 
     // Filter by viewport
     if (window->Viewport != g.MouseViewport)
-        if (g.MovingWindow == NULL || window->RootWindow != g.MovingWindow->RootWindow)
+        if (g.MovingWindow == NULL || window->RootWindowDockTree != g.MovingWindow->RootWindowDockTree)
             return false;
 
     return true;
@@ -3166,20 +3193,22 @@ bool ImGui::IsItemHovered(ImGuiHoveredFlags flags)
         return IsItemFocused();
 
     // Test for bounding box overlap, as updated as ItemAdd()
-    if (!(window->DC.LastItemStatusFlags & ImGuiItemStatusFlags_HoveredRect))
+    ImGuiItemStatusFlags status_flags = window->DC.LastItemStatusFlags;
+    if (!(status_flags & ImGuiItemStatusFlags_HoveredRect))
         return false;
     IM_ASSERT((flags & (ImGuiHoveredFlags_RootWindow | ImGuiHoveredFlags_ChildWindows)) == 0);   // Flags not supported by this function
 
     // Test if we are hovering the right window (our window could be behind another window)
-    // [2017/10/16] Reverted commit 344d48be3 and testing RootWindow instead. I believe it is correct to NOT test for RootWindow but this leaves us unable to use IsItemHovered() after EndChild() itself.
-    // Until a solution is found I believe reverting to the test from 2017/09/27 is safe since this was the test that has been running for a long while.
-    //if (g.HoveredWindow != window)
-    //    return false;
-    if (g.HoveredRootWindow != window->RootWindow && !(flags & ImGuiHoveredFlags_AllowWhenOverlapped))
-        return false;
+    // [2021/03/02] Reworked / reverted the revert, finally. Note we want e.g. BeginGroup/ItemAdd/EndGroup to work as well. (#3851)
+    // [2017/10/16] Reverted commit 344d48be3 and testing RootWindow instead. I believe it is correct to NOT test for RootWindow but this leaves us unable
+    // to use IsItemHovered() after EndChild() itself. Until a solution is found I believe reverting to the test from 2017/09/27 is safe since this was
+    // the test that has been running for a long while.
+    if (g.HoveredWindow != window && (status_flags & ImGuiItemStatusFlags_HoveredWindow) == 0)
+        if ((flags & ImGuiHoveredFlags_AllowWhenOverlapped) == 0)
+            return false;
 
     // Test if another item is active (e.g. being dragged)
-    if (!(flags & ImGuiHoveredFlags_AllowWhenBlockedByActiveItem))
+    if ((flags & ImGuiHoveredFlags_AllowWhenBlockedByActiveItem) == 0)
         if (g.ActiveId != 0 && g.ActiveId != window->DC.LastItemId && !g.ActiveIdAllowOverlap && g.ActiveId != window->MoveId)
             return false;
 
@@ -3274,18 +3303,18 @@ bool ImGui::FocusableItemRegister(ImGuiWindow* window, ImGuiID id)
 
     // Process TAB/Shift-TAB to tab *OUT* of the currently focused item.
     // (Note that we can always TAB out of a widget that doesn't allow tabbing in)
-    if (g.ActiveId == id && g.FocusTabPressed && !IsActiveIdUsingKey(ImGuiKey_Tab) && g.FocusRequestNextWindow == NULL)
+    if (g.ActiveId == id && g.TabFocusPressed && !IsActiveIdUsingKey(ImGuiKey_Tab) && g.TabFocusRequestNextWindow == NULL)
     {
-        g.FocusRequestNextWindow = window;
-        g.FocusRequestNextCounterTabStop = window->DC.FocusCounterTabStop + (g.IO.KeyShift ? (is_tab_stop ? -1 : 0) : +1); // Modulo on index will be applied at the end of frame once we've got the total counter of items.
+        g.TabFocusRequestNextWindow = window;
+        g.TabFocusRequestNextCounterTabStop = window->DC.FocusCounterTabStop + (g.IO.KeyShift ? (is_tab_stop ? -1 : 0) : +1); // Modulo on index will be applied at the end of frame once we've got the total counter of items.
     }
 
     // Handle focus requests
-    if (g.FocusRequestCurrWindow == window)
+    if (g.TabFocusRequestCurrWindow == window)
     {
-        if (window->DC.FocusCounterRegular == g.FocusRequestCurrCounterRegular)
+        if (window->DC.FocusCounterRegular == g.TabFocusRequestCurrCounterRegular)
             return true;
-        if (is_tab_stop && window->DC.FocusCounterTabStop == g.FocusRequestCurrCounterTabStop)
+        if (is_tab_stop && window->DC.FocusCounterTabStop == g.TabFocusRequestCurrCounterTabStop)
         {
             g.NavJustTabbedId = id;
             return true;
@@ -3334,7 +3363,7 @@ void* ImGui::MemAlloc(size_t size)
 {
     if (ImGuiContext* ctx = GImGui)
         ctx->IO.MetricsActiveAllocations++;
-    return GImAllocatorAllocFunc(size, GImAllocatorUserData);
+    return (*GImAllocatorAllocFunc)(size, GImAllocatorUserData);
 }
 
 // IM_FREE() == ImGui::MemFree()
@@ -3343,7 +3372,7 @@ void ImGui::MemFree(void* ptr)
     if (ptr)
         if (ImGuiContext* ctx = GImGui)
             ctx->IO.MetricsActiveAllocations--;
-    return GImAllocatorFreeFunc(ptr, GImAllocatorUserData);
+    return (*GImAllocatorFreeFunc)(ptr, GImAllocatorUserData);
 }
 
 const char* ImGui::GetClipboardText()
@@ -3380,13 +3409,21 @@ void ImGui::SetCurrentContext(ImGuiContext* ctx)
 #endif
 }
 
-void ImGui::SetAllocatorFunctions(void* (*alloc_func)(size_t sz, void* user_data), void (*free_func)(void* ptr, void* user_data), void* user_data)
+void ImGui::SetAllocatorFunctions(ImGuiMemAllocFunc alloc_func, ImGuiMemFreeFunc free_func, void* user_data)
 {
     GImAllocatorAllocFunc = alloc_func;
     GImAllocatorFreeFunc = free_func;
     GImAllocatorUserData = user_data;
 }
 
+// This is provided to facilitate copying allocators from one static/DLL boundary to another (e.g. retrieve default allocator of your executable address space)
+void ImGui::GetAllocatorFunctions(ImGuiMemAllocFunc* p_alloc_func, ImGuiMemFreeFunc* p_free_func, void** p_user_data)
+{
+    *p_alloc_func = GImAllocatorAllocFunc;
+    *p_free_func = GImAllocatorFreeFunc;
+    *p_user_data = GImAllocatorUserData;
+}
+
 ImGuiContext* ImGui::CreateContext(ImFontAtlas* shared_font_atlas)
 {
     ImGuiContext* ctx = IM_NEW(ImGuiContext)(shared_font_atlas);
@@ -3527,10 +3564,10 @@ void ImGui::StartMouseMovingWindow(ImGuiWindow* window)
     SetActiveID(window->MoveId, window);
     g.NavDisableHighlight = true;
     g.ActiveIdNoClearOnFocusLoss = true;
-    g.ActiveIdClickOffset = g.IO.MouseClickedPos[0] - window->RootWindow->Pos;
+    g.ActiveIdClickOffset = g.IO.MouseClickedPos[0] - window->RootWindowDockTree->Pos;
 
     bool can_move_window = true;
-    if ((window->Flags & ImGuiWindowFlags_NoMove) || (window->RootWindow->Flags & ImGuiWindowFlags_NoMove))
+    if ((window->Flags & ImGuiWindowFlags_NoMove) || (window->RootWindowDockTree->Flags & ImGuiWindowFlags_NoMove))
         can_move_window = false;
     if (ImGuiDockNode* node = window->DockNodeAsHost)
         if (node->VisibleWindow && (node->VisibleWindow->Flags & ImGuiWindowFlags_NoMove))
@@ -3578,8 +3615,8 @@ void ImGui::UpdateMouseMovingWindowNewFrame()
         // We actually want to move the root window. g.MovingWindow == window we clicked on (could be a child window).
         // We track it to preserve Focus and so that generally ActiveIdWindow == MovingWindow and ActiveId == MovingWindow->MoveId for consistency.
         KeepAliveID(g.ActiveId);
-        IM_ASSERT(g.MovingWindow && g.MovingWindow->RootWindow);
-        ImGuiWindow* moving_window = g.MovingWindow->RootWindow;
+        IM_ASSERT(g.MovingWindow && g.MovingWindow->RootWindowDockTree);
+        ImGuiWindow* moving_window = g.MovingWindow->RootWindowDockTree;
         if (g.IO.MouseDown[0] && IsMousePosValid(&g.IO.MousePos))
         {
             ImVec2 pos = g.IO.MousePos - g.ActiveIdClickOffset;
@@ -3643,7 +3680,7 @@ void ImGui::UpdateMouseMovingWindowEndFrame()
     {
         // Handle the edge case of a popup being closed while clicking in its empty space.
         // If we try to focus it, FocusWindow() > ClosePopupsOverWindow() will accidentally close any parent popups because they are not linked together any more.
-        ImGuiWindow* root_window = g.HoveredWindow ? g.HoveredWindow->RootWindowDockStop : NULL;
+        ImGuiWindow* root_window = g.HoveredWindow ? g.HoveredWindow->RootWindow : NULL;
         const bool is_closed_popup = root_window && (root_window->Flags & ImGuiWindowFlags_Popup) && !IsPopupOpen(root_window->PopupId, ImGuiPopupFlags_AnyPopupLevel);
 
         if (root_window != NULL && !is_closed_popup)
@@ -3809,7 +3846,7 @@ void ImGui::UpdateMouseWheel()
         const float new_font_scale = ImClamp(window->FontWindowScale + g.IO.MouseWheel * 0.10f, 0.50f, 2.50f);
         const float scale = new_font_scale / window->FontWindowScale;
         window->FontWindowScale = new_font_scale;
-        if (!(window->Flags & ImGuiWindowFlags_ChildWindow))
+        if (window == window->RootWindow)
         {
             const ImVec2 offset = window->Size * (1.0f - scale) * (g.IO.MousePos - window->Pos) / window->Size;
             SetWindowPos(window, window->Pos + offset, 0);
@@ -3858,32 +3895,32 @@ void ImGui::UpdateTabFocus()
     ImGuiContext& g = *GImGui;
 
     // Pressing TAB activate widget focus
-    g.FocusTabPressed = (g.NavWindow && g.NavWindow->Active && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs) && !g.IO.KeyCtrl && IsKeyPressedMap(ImGuiKey_Tab));
-    if (g.ActiveId == 0 && g.FocusTabPressed)
+    g.TabFocusPressed = (g.NavWindow && g.NavWindow->Active && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs) && !g.IO.KeyCtrl && IsKeyPressedMap(ImGuiKey_Tab));
+    if (g.ActiveId == 0 && g.TabFocusPressed)
     {
         // Note that SetKeyboardFocusHere() sets the Next fields mid-frame. To be consistent we also
         // manipulate the Next fields even, even though they will be turned into Curr fields by the code below.
-        g.FocusRequestNextWindow = g.NavWindow;
-        g.FocusRequestNextCounterRegular = INT_MAX;
+        g.TabFocusRequestNextWindow = g.NavWindow;
+        g.TabFocusRequestNextCounterRegular = INT_MAX;
         if (g.NavId != 0 && g.NavIdTabCounter != INT_MAX)
-            g.FocusRequestNextCounterTabStop = g.NavIdTabCounter + 1 + (g.IO.KeyShift ? -1 : 1);
+            g.TabFocusRequestNextCounterTabStop = g.NavIdTabCounter + 1 + (g.IO.KeyShift ? -1 : 1);
         else
-            g.FocusRequestNextCounterTabStop = g.IO.KeyShift ? -1 : 0;
+            g.TabFocusRequestNextCounterTabStop = g.IO.KeyShift ? -1 : 0;
     }
 
     // Turn queued focus request into current one
-    g.FocusRequestCurrWindow = NULL;
-    g.FocusRequestCurrCounterRegular = g.FocusRequestCurrCounterTabStop = INT_MAX;
-    if (g.FocusRequestNextWindow != NULL)
+    g.TabFocusRequestCurrWindow = NULL;
+    g.TabFocusRequestCurrCounterRegular = g.TabFocusRequestCurrCounterTabStop = INT_MAX;
+    if (g.TabFocusRequestNextWindow != NULL)
     {
-        ImGuiWindow* window = g.FocusRequestNextWindow;
-        g.FocusRequestCurrWindow = window;
-        if (g.FocusRequestNextCounterRegular != INT_MAX && window->DC.FocusCounterRegular != -1)
-            g.FocusRequestCurrCounterRegular = ImModPositive(g.FocusRequestNextCounterRegular, window->DC.FocusCounterRegular + 1);
-        if (g.FocusRequestNextCounterTabStop != INT_MAX && window->DC.FocusCounterTabStop != -1)
-            g.FocusRequestCurrCounterTabStop = ImModPositive(g.FocusRequestNextCounterTabStop, window->DC.FocusCounterTabStop + 1);
-        g.FocusRequestNextWindow = NULL;
-        g.FocusRequestNextCounterRegular = g.FocusRequestNextCounterTabStop = INT_MAX;
+        ImGuiWindow* window = g.TabFocusRequestNextWindow;
+        g.TabFocusRequestCurrWindow = window;
+        if (g.TabFocusRequestNextCounterRegular != INT_MAX && window->DC.FocusCounterRegular != -1)
+            g.TabFocusRequestCurrCounterRegular = ImModPositive(g.TabFocusRequestNextCounterRegular, window->DC.FocusCounterRegular + 1);
+        if (g.TabFocusRequestNextCounterTabStop != INT_MAX && window->DC.FocusCounterTabStop != -1)
+            g.TabFocusRequestCurrCounterTabStop = ImModPositive(g.TabFocusRequestNextCounterTabStop, window->DC.FocusCounterTabStop + 1);
+        g.TabFocusRequestNextWindow = NULL;
+        g.TabFocusRequestNextCounterRegular = g.TabFocusRequestNextCounterTabStop = INT_MAX;
     }
 
     g.NavIdTabCounter = INT_MAX;
@@ -3904,7 +3941,7 @@ void ImGui::UpdateHoveredWindowAndCaptureFlags()
 
     // Modal windows prevents mouse from hovering behind them.
     ImGuiWindow* modal_window = GetTopMostPopupModal();
-    if (modal_window && g.HoveredRootWindow && !IsWindowChildOf(g.HoveredRootWindow, modal_window))
+    if (modal_window && g.HoveredWindow && !IsWindowChildOf(g.HoveredWindow->RootWindowDockTree, modal_window))
         clear_hovered_windows = true;
 
     // Disabled mouse?
@@ -3932,7 +3969,7 @@ void ImGui::UpdateHoveredWindowAndCaptureFlags()
         clear_hovered_windows = true;
 
     if (clear_hovered_windows)
-        g.HoveredWindow = g.HoveredRootWindow = g.HoveredWindowUnderMovingWindow = NULL;
+        g.HoveredWindow = g.HoveredWindowUnderMovingWindow = NULL;
 
     // Update io.WantCaptureMouse for the user application (true = dispatch mouse info to imgui, false = dispatch mouse info to Dear ImGui + app)
     if (g.WantCaptureMouseNextFrame != -1)
@@ -3967,7 +4004,7 @@ void ImGui::NewFrame()
 {
     IM_ASSERT(GImGui != NULL && "No current context. Did you call ImGui::CreateContext() and ImGui::SetCurrentContext() ?");
     ImGuiContext& g = *GImGui;
-    
+
     // Remove pending delete hooks before frame start.
     // This deferred removal avoid issues of removal while iterating the hook vector
     for (int n = g.Hooks.Size - 1; n >= 0; n--)
@@ -4009,7 +4046,7 @@ void ImGui::NewFrame()
         virtual_space.Add(g.Viewports[n]->GetMainRect());
     g.DrawListSharedData.ClipRectFullscreen = virtual_space.ToVec4();
     g.DrawListSharedData.CurveTessellationTol = g.Style.CurveTessellationTol;
-    g.DrawListSharedData.SetCircleSegmentMaxError(g.Style.CircleSegmentMaxError);
+    g.DrawListSharedData.SetCircleTessellationMaxError(g.Style.CircleTessellationMaxError);
     g.DrawListSharedData.InitialFlags = ImDrawListFlags_None;
     if (g.Style.AntiAliasedLines)
         g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedLines;
@@ -4284,7 +4321,7 @@ void ImGui::Shutdown(ImGuiContext* context)
     g.CurrentWindowStack.clear();
     g.WindowsById.Clear();
     g.NavWindow = NULL;
-    g.HoveredWindow = g.HoveredRootWindow = g.HoveredWindowUnderMovingWindow = NULL;
+    g.HoveredWindow = g.HoveredWindowUnderMovingWindow = NULL;
     g.ActiveIdWindow = g.ActiveIdPreviousFrameWindow = NULL;
     g.MovingWindow = NULL;
     g.ColorStack.clear();
@@ -4516,15 +4553,15 @@ static void ImGui::EndFrameDrawDimmedBackgrounds()
         // Choose a draw list that will be front-most across all our children
         // In the unlikely case that the window wasn't made active we can't rely on its drawlist and skip rendering all-together.
         ImGuiWindow* window = g.NavWindowingTargetAnim;
-        ImDrawList* draw_list = FindFrontMostVisibleChildWindow(window->RootWindow)->DrawList;
+        ImDrawList* draw_list = FindFrontMostVisibleChildWindow(window->RootWindowDockTree)->DrawList;
         draw_list->PushClipRectFullScreen();
 
         // Docking: draw modal whitening background on other nodes of a same dock tree
         // For CTRL+TAB within a docking node we need to render the dimming background in 8 steps
         // (Because the root node renders the background in one shot, in order to avoid flickering when a child dock node is not submitted)
-        if (window->RootWindowDockStop->DockIsActive)
-            if (window->RootWindow != window->RootWindowDockStop)
-                RenderRectFilledWithHole(draw_list, window->RootWindow->Rect(), window->RootWindowDockStop->Rect(), GetColorU32(ImGuiCol_NavWindowingDimBg, g.DimBgRatio), g.Style.WindowRounding);
+        if (window->RootWindow->DockIsActive)
+            if (window->RootWindowDockTree != window->RootWindow)
+                RenderRectFilledWithHole(draw_list, window->RootWindowDockTree->Rect(), window->RootWindow->Rect(), GetColorU32(ImGuiCol_NavWindowingDimBg, g.DimBgRatio), g.Style.WindowRounding);
 
         // Draw navigation selection/windowing rectangle border
         float rounding = ImMax(window->WindowRounding, g.Style.WindowRounding);
@@ -4656,7 +4693,7 @@ void ImGui::Render()
 
     // Add ImDrawList to render
     ImGuiWindow* windows_to_render_top_most[2];
-    windows_to_render_top_most[0] = (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoBringToFrontOnFocus)) ? g.NavWindowingTarget->RootWindow : NULL;
+    windows_to_render_top_most[0] = (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoBringToFrontOnFocus)) ? g.NavWindowingTarget->RootWindowDockTree : NULL;
     windows_to_render_top_most[1] = (g.NavWindowingTarget ? g.NavWindowingListWindow : NULL);
     for (int n = 0; n != g.Windows.Size; n++)
     {
@@ -4781,14 +4818,13 @@ static void FindHoveredWindow()
 
         if (hovered_window == NULL)
             hovered_window = window;
-        if (hovered_window_ignoring_moving_window == NULL && (!g.MovingWindow || window->RootWindow != g.MovingWindow->RootWindow))
+        if (hovered_window_ignoring_moving_window == NULL && (!g.MovingWindow || window->RootWindowDockTree != g.MovingWindow->RootWindowDockTree))
             hovered_window_ignoring_moving_window = window;
         if (hovered_window && hovered_window_ignoring_moving_window)
             break;
     }
 
     g.HoveredWindow = hovered_window;
-    g.HoveredRootWindow = g.HoveredWindow ? g.HoveredWindow->RootWindow : NULL;
     g.HoveredWindowUnderMovingWindow = hovered_window_ignoring_moving_window;
 
     if (g.MovingWindow)
@@ -5077,6 +5113,8 @@ bool ImGui::IsItemFocused()
     return true;
 }
 
+// Important: this can be useful but it is NOT equivalent to the behavior of e.g.Button()!
+// Most widgets have specific reactions based on mouse-up/down state, mouse position etc.
 bool ImGui::IsItemClicked(ImGuiMouseButton mouse_button)
 {
     return IsMouseClicked(mouse_button) && IsItemHovered(ImGuiHoveredFlags_None);
@@ -5265,6 +5303,8 @@ void ImGui::EndChild()
             // Not navigable into
             ItemAdd(bb, 0);
         }
+        if (g.HoveredWindow == window)
+            parent_window->DC.LastItemStatusFlags |= ImGuiItemStatusFlags_HoveredWindow;
     }
     g.WithinEndChild = false;
     g.LogLinePosY = -FLT_MAX; // To enforce a carriage return
@@ -5385,9 +5425,10 @@ static ImGuiWindow* GetWindowForTitleAndMenuHeight(ImGuiWindow* window)
     return (window->DockNodeAsHost && window->DockNodeAsHost->VisibleWindow) ? window->DockNodeAsHost->VisibleWindow : window;
 }
 
-static ImVec2 CalcWindowSizeAfterConstraint(ImGuiWindow* window, ImVec2 new_size)
+static ImVec2 CalcWindowSizeAfterConstraint(ImGuiWindow* window, const ImVec2& size_desired)
 {
     ImGuiContext& g = *GImGui;
+    ImVec2 new_size = size_desired;
     if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasSizeConstraint)
     {
         // Using -1,-1 on either X/Y axis to preserve the current size.
@@ -5670,12 +5711,12 @@ static bool ImGui::UpdateWindowManualResize(ImGuiWindow* window, const ImVec2& s
     window->DC.NavLayerCurrent = ImGuiNavLayer_Main;
 
     // Navigation resize (keyboard/gamepad)
-    if (g.NavWindowingTarget && g.NavWindowingTarget->RootWindow == window)
+    if (g.NavWindowingTarget && g.NavWindowingTarget->RootWindowDockTree == window)
     {
         ImVec2 nav_resize_delta;
-        if (g.NavInputSource == ImGuiInputSource_NavKeyboard && g.IO.KeyShift)
+        if (g.NavInputSource == ImGuiInputSource_Keyboard && g.IO.KeyShift)
             nav_resize_delta = GetNavInputAmount2d(ImGuiNavDirSourceFlags_Keyboard, ImGuiInputReadMode_Down);
-        if (g.NavInputSource == ImGuiInputSource_NavGamepad)
+        if (g.NavInputSource == ImGuiInputSource_Gamepad)
             nav_resize_delta = GetNavInputAmount2d(ImGuiNavDirSourceFlags_PadDPad, ImGuiInputReadMode_Down);
         if (nav_resize_delta.x != 0.0f || nav_resize_delta.y != 0.0f)
         {
@@ -5721,7 +5762,7 @@ static void ImGui::RenderWindowOuterBorders(ImGuiWindow* window)
     float rounding = window->WindowRounding;
     float border_size = window->WindowBorderSize;
     if (border_size > 0.0f && !(window->Flags & ImGuiWindowFlags_NoBackground))
-        window->DrawList->AddRect(window->Pos, window->Pos + window->Size, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+        window->DrawList->AddRect(window->Pos, window->Pos + window->Size, GetColorU32(ImGuiCol_Border), rounding, 0, border_size);
 
     int border_held = window->ResizeBorderHeld;
     if (border_held != -1)
@@ -5730,7 +5771,7 @@ static void ImGui::RenderWindowOuterBorders(ImGuiWindow* window)
         ImRect border_r = GetResizeBorderRect(window, border_held, rounding, 0.0f);
         window->DrawList->PathArcTo(ImLerp(border_r.Min, border_r.Max, def.CornerPosN1) + ImVec2(0.5f, 0.5f) + def.InnerDir * rounding, rounding, def.OuterAngle - IM_PI * 0.25f, def.OuterAngle);
         window->DrawList->PathArcTo(ImLerp(border_r.Min, border_r.Max, def.CornerPosN2) + ImVec2(0.5f, 0.5f) + def.InnerDir * rounding, rounding, def.OuterAngle, def.OuterAngle + IM_PI * 0.25f);
-        window->DrawList->PathStroke(GetColorU32(ImGuiCol_SeparatorActive), false, ImMax(2.0f, border_size)); // Thicker than usual
+        window->DrawList->PathStroke(GetColorU32(ImGuiCol_SeparatorActive), 0, ImMax(2.0f, border_size)); // Thicker than usual
     }
     if (g.Style.FrameBorderSize > 0 && !(window->Flags & ImGuiWindowFlags_NoTitleBar) && !window->DockIsActive)
     {
@@ -5800,7 +5841,7 @@ void ImGui::RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar
                 if (override_alpha)
                     bg_col = (bg_col & ~IM_COL32_A_MASK) | (IM_F32_TO_INT8_SAT(alpha) << IM_COL32_A_SHIFT);
             }
-            window->DrawList->AddRectFilled(window->Pos + ImVec2(0, window->TitleBarHeight()), window->Pos + window->Size, bg_col, window_rounding, (flags & ImGuiWindowFlags_NoTitleBar) ? ImDrawCornerFlags_All : ImDrawCornerFlags_Bot);
+            window->DrawList->AddRectFilled(window->Pos + ImVec2(0, window->TitleBarHeight()), window->Pos + window->Size, bg_col, window_rounding, (flags & ImGuiWindowFlags_NoTitleBar) ? 0 : ImDrawFlags_RoundCornersBottom);
         }
 
         // Title bar
@@ -5809,7 +5850,7 @@ void ImGui::RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar
         if (!(flags & ImGuiWindowFlags_NoTitleBar) && !window->DockIsActive)
         {
             ImU32 title_bar_col = GetColorU32(title_bar_is_highlight ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg);
-            window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, window_rounding, ImDrawCornerFlags_Top);
+            window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, window_rounding, ImDrawFlags_RoundCornersTop);
         }
 
         // Menu bar
@@ -5817,7 +5858,7 @@ void ImGui::RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar
         {
             ImRect menu_bar_rect = window->MenuBarRect();
             menu_bar_rect.ClipWith(window->Rect());  // Soft clipping, in particular child window don't have minimum size covering the menu bar so this is useful for them.
-            window->DrawList->AddRectFilled(menu_bar_rect.Min + ImVec2(window_border_size, 0), menu_bar_rect.Max - ImVec2(window_border_size, 0), GetColorU32(ImGuiCol_MenuBarBg), (flags & ImGuiWindowFlags_NoTitleBar) ? window_rounding : 0.0f, ImDrawCornerFlags_Top);
+            window->DrawList->AddRectFilled(menu_bar_rect.Min + ImVec2(window_border_size, 0), menu_bar_rect.Max - ImVec2(window_border_size, 0), GetColorU32(ImGuiCol_MenuBarBg), (flags & ImGuiWindowFlags_NoTitleBar) ? window_rounding : 0.0f, ImDrawFlags_RoundCornersTop);
             if (style.FrameBorderSize > 0.0f && menu_bar_rect.Max.y < window->Pos.y + window->Size.y)
                 window->DrawList->AddLine(menu_bar_rect.GetBL(), menu_bar_rect.GetBR(), GetColorU32(ImGuiCol_Border), style.FrameBorderSize);
         }
@@ -5955,12 +5996,12 @@ void ImGui::RenderWindowTitleBarContents(ImGuiWindow* window, const ImRect& titl
 void ImGui::UpdateWindowParentAndRootLinks(ImGuiWindow* window, ImGuiWindowFlags flags, ImGuiWindow* parent_window)
 {
     window->ParentWindow = parent_window;
-    window->RootWindow = window->RootWindowDockStop = window->RootWindowForTitleBarHighlight = window->RootWindowForNav = window;
+    window->RootWindow = window->RootWindowDockTree = window->RootWindowForTitleBarHighlight = window->RootWindowForNav = window;
     if (parent_window && (flags & ImGuiWindowFlags_ChildWindow) && !(flags & ImGuiWindowFlags_Tooltip))
     {
-        window->RootWindow = parent_window->RootWindow;
+        window->RootWindowDockTree = parent_window->RootWindowDockTree;
         if (!window->DockIsActive && !(parent_window->Flags & ImGuiWindowFlags_DockNodeHost))
-            window->RootWindowDockStop = parent_window->RootWindowDockStop;
+            window->RootWindow = parent_window->RootWindow;
     }
     if (parent_window && !(flags & ImGuiWindowFlags_Modal) && (flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_Popup)))
         window->RootWindowForTitleBarHighlight = parent_window->RootWindowForTitleBarHighlight;
@@ -6076,9 +6117,6 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         window->PopupId = popup_ref.PopupId;
     }
 
-    if (window_just_appearing_after_hidden_for_resize && !(flags & ImGuiWindowFlags_ChildWindow))
-        window->NavLastIds[0] = 0;
-
     // Update ->RootWindow and others pointers (before any possible call to FocusWindow)
     if (first_begin_of_the_frame)
         UpdateWindowParentAndRootLinks(window, flags, parent_window);
@@ -6232,7 +6270,6 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             {
                 window->Collapsed = !window->Collapsed;
                 MarkIniSettingsDirty(window);
-                FocusWindow(window);
             }
         }
         else
@@ -6402,9 +6439,11 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             if (window->WindowClass.ViewportFlagsOverrideClear)
                 viewport_flags &= ~window->WindowClass.ViewportFlagsOverrideClear;
 
-            // We also tell the backend that clearing the platform window won't be necessary, as our window is filling the viewport and we have disabled BgAlpha
+            // We can also tell the backend that clearing the platform window won't be necessary,
+            // as our window background is filling the viewport and we have disabled BgAlpha.
+            // FIXME: Work on support for per-viewport transparency (#2766)
             if (!(flags & ImGuiWindowFlags_NoBackground))
-                viewport_flags &= ~ImGuiViewportFlags_NoRendererClear;
+                viewport_flags |= ImGuiViewportFlags_NoRendererClear;
 
             window->Viewport->Flags = viewport_flags;
         }
@@ -6427,19 +6466,11 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             }
             else if (window->ViewportOwned && g.PlatformIO.Monitors.Size > 0)
             {
-                if (window->Viewport->PlatformMonitor == -1)
-                {
-                    // Fallback for "lost" window (e.g. a monitor disconnected): we move the window back over the main viewport
-                    const ImGuiViewport* main_viewport = GetMainViewport();
-                    SetWindowPos(window, main_viewport->Pos + style.DisplayWindowPadding, ImGuiCond_Always);
-                }
-                else
-                {
-                    ImGuiPlatformMonitor& monitor = g.PlatformIO.Monitors[window->Viewport->PlatformMonitor];
-                    visibility_rect.Min = monitor.WorkPos + visibility_padding;
-                    visibility_rect.Max = monitor.WorkPos + monitor.WorkSize - visibility_padding;
-                    ClampWindowRect(window, visibility_rect);
-                }
+                // Lost windows (e.g. a monitor disconnected) will naturally moved to the fallback/dummy monitor aka the main viewport.
+                const ImGuiPlatformMonitor* monitor = GetViewportPlatformMonitor(window->Viewport);
+                visibility_rect.Min = monitor->WorkPos + visibility_padding;
+                visibility_rect.Max = monitor->WorkPos + monitor->WorkSize - visibility_padding;
+                ClampWindowRect(window, visibility_rect);
             }
         }
         window->Pos = ImFloor(window->Pos);
@@ -6582,7 +6613,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         // Draw modal or window list full viewport dimming background (for other viewports we'll render them in EndFrame)
         ImGuiWindow* window_window_list = g.NavWindowingListWindow;
         const bool dim_bg_for_modal = (flags & ImGuiWindowFlags_Modal) && window == GetTopMostPopupModal() && window->HiddenFramesCannotSkipItems <= 0;
-        const bool dim_bg_for_window_list = g.NavWindowingTargetAnim && ((window == g.NavWindowingTargetAnim->RootWindow) || (window == window_window_list && window_window_list->Viewport != g.NavWindowingTargetAnim->Viewport));
+        const bool dim_bg_for_window_list = g.NavWindowingTargetAnim && ((window == g.NavWindowingTargetAnim->RootWindowDockTree) || (window == window_window_list && window_window_list->Viewport != g.NavWindowingTargetAnim->Viewport));
         if (dim_bg_for_modal || dim_bg_for_window_list)
         {
             const ImU32 dim_bg_col = GetColorU32(dim_bg_for_modal ? ImGuiCol_ModalWindowDimBg : ImGuiCol_NavWindowingDimBg, g.DimBgRatio);
@@ -6633,7 +6664,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
                 bb.Expand(-g.FontSize - 1.0f);
                 rounding = window->WindowRounding;
             }
-            window->DrawList->AddRect(bb.Min, bb.Max, GetColorU32(ImGuiCol_NavWindowingHighlight, g.NavWindowingHighlightAlpha), rounding, ~0, 3.0f);
+            window->DrawList->AddRect(bb.Min, bb.Max, GetColorU32(ImGuiCol_NavWindowingHighlight, g.NavWindowingHighlightAlpha), rounding, 0, 3.0f);
         }
 
         // UPDATE RECTANGLES (2- THOSE AFFECTED BY SCROLLING)
@@ -6706,7 +6737,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         if (want_focus)
         {
             FocusWindow(window);
-            NavInitWindow(window, false);
+            NavInitWindow(window, false); // <-- this is in the way for us to be able to defer and sort reappearing FocusWindow() calls
         }
 
         // Close requested by platform window
@@ -6743,13 +6774,13 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             // Docking: Dragging a dockable window (or any of its child) turns it into a drag and drop source.
             // We need to do this _before_ we overwrite window->DC.LastItemId below because BeginDockableDragDropSource() also overwrites it.
             if ((g.MovingWindow == window) && (g.IO.ConfigDockingWithShift == g.IO.KeyShift))
-                if ((window->RootWindow->Flags & ImGuiWindowFlags_NoDocking) == 0)
+                if ((window->RootWindowDockTree->Flags & ImGuiWindowFlags_NoDocking) == 0)
                     BeginDockableDragDropSource(window);
 
             // Docking: Any dockable window can act as a target. For dock node hosts we call BeginDockableDragDropTarget() in DockNodeUpdate() instead.
             if (g.DragDropActive && !(flags & ImGuiWindowFlags_NoDocking))
-                if (g.MovingWindow == NULL || g.MovingWindow->RootWindow != window)
-                    if ((window == window->RootWindow) && !(window->Flags & ImGuiWindowFlags_DockNodeHost))
+                if (g.MovingWindow == NULL || g.MovingWindow->RootWindowDockTree != window)
+                    if ((window == window->RootWindowDockTree) && !(window->Flags & ImGuiWindowFlags_DockNodeHost))
                         BeginDockableDragDropTarget(window);
         }
 
@@ -6823,6 +6854,13 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         // Update the Hidden flag
         window->Hidden = (window->HiddenFramesCanSkipItems > 0) || (window->HiddenFramesCannotSkipItems > 0) || (window->HiddenFramesForRenderOnly > 0);
 
+        // Disable inputs for requested number of frames
+        if (window->DisableInputsFrames > 0)
+        {
+            window->DisableInputsFrames--;
+            window->Flags |= ImGuiWindowFlags_NoInputs;
+        }
+
         // Update the SkipItems flag, used to early out of all items functions (no layout required)
         bool skip_items = false;
         if (window->Collapsed || !window->Active || window->Hidden)
@@ -6894,7 +6932,7 @@ void ImGui::BringWindowToDisplayFront(ImGuiWindow* window)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* current_front_window = g.Windows.back();
-    if (current_front_window == window || current_front_window->RootWindow == window) // Cheap early out (could be better)
+    if (current_front_window == window || current_front_window->RootWindowDockTree == window) // Cheap early out (could be better)
         return;
     for (int i = g.Windows.Size - 2; i >= 0; i--) // We can ignore the top-most window
         if (g.Windows[i] == window)
@@ -6929,11 +6967,12 @@ void ImGui::FocusWindow(ImGuiWindow* window)
         g.NavWindow = window;
         if (window && g.NavDisableMouseHover)
             g.NavMousePosDirty = true;
-        g.NavInitRequest = false;
         g.NavId = window ? window->NavLastIds[0] : 0; // Restore NavId
         g.NavFocusScopeId = 0;
         g.NavIdIsAlive = false;
         g.NavLayer = ImGuiNavLayer_Main;
+        g.NavInitRequest = g.NavMoveRequest = false;
+        NavUpdateAnyRequestFlag();
         //IMGUI_DEBUG_LOG("FocusWindow(\"%s\")\n", window ? window->Name : NULL);
     }
 
@@ -6941,9 +6980,9 @@ void ImGui::FocusWindow(ImGuiWindow* window)
     ClosePopupsOverWindow(window, false);
 
     // Move the root window to the top of the pile
-    IM_ASSERT(window == NULL || window->RootWindow != NULL);
-    ImGuiWindow* focus_front_window = window ? window->RootWindowDockStop : NULL;
-    ImGuiWindow* display_front_window = window ? window->RootWindow : NULL;
+    IM_ASSERT(window == NULL || window->RootWindowDockTree != NULL);
+    ImGuiWindow* focus_front_window = window ? window->RootWindow : NULL;
+    ImGuiWindow* display_front_window = window ? window->RootWindowDockTree : NULL;
     ImGuiDockNode* dock_node = window ? window->DockNode : NULL;
     bool active_id_window_is_dock_node_host = (g.ActiveIdWindow && dock_node && dock_node->HostWindow == g.ActiveIdWindow);
 
@@ -6951,7 +6990,7 @@ void ImGui::FocusWindow(ImGuiWindow* window)
     // - Focus a window while an InputText in another window is active, if focus happens before the old InputText can run.
     // - When using Nav to activate menu items (due to timing of activating on press->new window appears->losing ActiveId)
     // - Using dock host items (tab, collapse button) can trigger this before we redirect the ActiveIdWindow toward the child window.
-    if (g.ActiveId != 0 && g.ActiveIdWindow && g.ActiveIdWindow->RootWindowDockStop != focus_front_window)
+    if (g.ActiveId != 0 && g.ActiveIdWindow && g.ActiveIdWindow->RootWindow != focus_front_window)
         if (!g.ActiveIdNoClearOnFocusLoss && !active_id_window_is_dock_node_host)
             ClearActiveID();
 
@@ -6985,7 +7024,7 @@ void ImGui::FocusTopMostWindowUnderOne(ImGuiWindow* under_this_window, ImGuiWind
     {
         // We may later decide to test for different NoXXXInputs based on the active navigation input (mouse vs nav) but that may feel more confusing to the user.
         ImGuiWindow* window = g.WindowsFocusOrder[i];
-        if (window != ignore_window && window->WasActive && window->RootWindowDockStop == window)
+        if (window != ignore_window && window->WasActive && window->RootWindow == window)
             if ((window->Flags & (ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs)) != (ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs))
             {
                 // FIXME-DOCK: This is failing (lagging by one frame) for docked windows.
@@ -7000,6 +7039,7 @@ void ImGui::FocusTopMostWindowUnderOne(ImGuiWindow* under_this_window, ImGuiWind
     FocusWindow(NULL);
 }
 
+// Important: this alone doesn't alter current ImDrawList state. This is called by PushFont/PopFont only.
 void ImGui::SetCurrentFont(ImFont* font)
 {
     ImGuiContext& g = *GImGui;
@@ -7094,7 +7134,7 @@ void ImGui::PopTextWrapPos()
 
 bool ImGui::IsWindowChildOf(ImGuiWindow* window, ImGuiWindow* potential_parent)
 {
-    if (window->RootWindow == potential_parent)
+    if (window->RootWindowDockTree == potential_parent)
         return true;
     while (window != NULL)
     {
@@ -7123,30 +7163,28 @@ bool ImGui::IsWindowHovered(ImGuiHoveredFlags flags)
 {
     IM_ASSERT((flags & ImGuiHoveredFlags_AllowWhenOverlapped) == 0);   // Flags not supported by this function
     ImGuiContext& g = *GImGui;
+    if (g.HoveredWindow == NULL)
+        return false;
 
-    if (flags & ImGuiHoveredFlags_AnyWindow)
-    {
-        if (g.HoveredWindow == NULL)
-            return false;
-    }
-    else
+    if ((flags & ImGuiHoveredFlags_AnyWindow) == 0)
     {
+        ImGuiWindow* window = g.CurrentWindow;
         switch (flags & (ImGuiHoveredFlags_RootWindow | ImGuiHoveredFlags_ChildWindows))
         {
         case ImGuiHoveredFlags_RootWindow | ImGuiHoveredFlags_ChildWindows:
-            if (g.HoveredWindow == NULL || g.HoveredWindow->RootWindowDockStop != g.CurrentWindow->RootWindowDockStop)
+            if (g.HoveredWindow->RootWindow != window->RootWindow)
                 return false;
             break;
         case ImGuiHoveredFlags_RootWindow:
-            if (g.HoveredWindow != g.CurrentWindow->RootWindowDockStop)
+            if (g.HoveredWindow != window->RootWindow)
                 return false;
             break;
         case ImGuiHoveredFlags_ChildWindows:
-            if (g.HoveredWindow == NULL || !IsWindowChildOf(g.HoveredWindow, g.CurrentWindow))
+            if (!IsWindowChildOf(g.HoveredWindow, window))
                 return false;
             break;
         default:
-            if (g.HoveredWindow != g.CurrentWindow)
+            if (g.HoveredWindow != window)
                 return false;
             break;
         }
@@ -7171,9 +7209,9 @@ bool ImGui::IsWindowFocused(ImGuiFocusedFlags flags)
     switch (flags & (ImGuiFocusedFlags_RootWindow | ImGuiFocusedFlags_ChildWindows))
     {
     case ImGuiFocusedFlags_RootWindow | ImGuiFocusedFlags_ChildWindows:
-        return g.NavWindow && g.NavWindow->RootWindowDockStop == g.CurrentWindow->RootWindowDockStop;
+        return g.NavWindow && g.NavWindow->RootWindow == g.CurrentWindow->RootWindow;
     case ImGuiFocusedFlags_RootWindow:
-        return g.NavWindow == g.CurrentWindow->RootWindowDockStop;
+        return g.NavWindow == g.CurrentWindow->RootWindow;
     case ImGuiFocusedFlags_ChildWindows:
         return g.NavWindow && IsWindowChildOf(g.NavWindow, g.CurrentWindow);
     default:
@@ -7198,7 +7236,7 @@ bool ImGui::IsWindowDocked()
 // If you want a window to never be focused, you may use the e.g. NoInputs flag.
 bool ImGui::IsWindowNavFocusable(ImGuiWindow* window)
 {
-    return window->WasActive && window == window->RootWindowDockStop && !(window->Flags & ImGuiWindowFlags_NoNavFocus);
+    return window->WasActive && window == window->RootWindow && !(window->Flags & ImGuiWindowFlags_NoNavFocus);
 }
 
 float ImGui::GetWindowWidth()
@@ -7521,9 +7559,9 @@ void ImGui::SetKeyboardFocusHere(int offset)
     IM_ASSERT(offset >= -1);    // -1 is allowed but not below
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
-    g.FocusRequestNextWindow = window;
-    g.FocusRequestNextCounterRegular = window->DC.FocusCounterRegular + 1 + offset;
-    g.FocusRequestNextCounterTabStop = INT_MAX;
+    g.TabFocusRequestNextWindow = window;
+    g.TabFocusRequestNextCounterRegular = window->DC.FocusCounterRegular + 1 + offset;
+    g.TabFocusRequestNextCounterTabStop = INT_MAX;
 }
 
 void ImGui::SetItemDefaultFocus()
@@ -7690,7 +7728,7 @@ static void ImGui::ErrorCheckNewFrameSanityChecks()
     IM_ASSERT(g.IO.Fonts->Fonts.Size > 0                                && "Font Atlas not built. Did you call io.Fonts->GetTexDataAsRGBA32() / GetTexDataAsAlpha8()?");
     IM_ASSERT(g.IO.Fonts->Fonts[0]->IsLoaded()                          && "Font Atlas not built. Did you call io.Fonts->GetTexDataAsRGBA32() / GetTexDataAsAlpha8()?");
     IM_ASSERT(g.Style.CurveTessellationTol > 0.0f                       && "Invalid style setting!");
-    IM_ASSERT(g.Style.CircleSegmentMaxError > 0.0f                      && "Invalid style setting!");
+    IM_ASSERT(g.Style.CircleTessellationMaxError  > 0.0f                && "Invalid style setting!");
     IM_ASSERT(g.Style.Alpha >= 0.0f && g.Style.Alpha <= 1.0f            && "Invalid style setting!"); // Allows us to avoid a few clamps in color computations
     IM_ASSERT(g.Style.WindowMinSize.x >= 1.0f && g.Style.WindowMinSize.y >= 1.0f && "Invalid style setting.");
     IM_ASSERT(g.Style.WindowMenuButtonPosition == ImGuiDir_None || g.Style.WindowMenuButtonPosition == ImGuiDir_Left || g.Style.WindowMenuButtonPosition == ImGuiDir_Right);
@@ -8303,6 +8341,7 @@ void ImGui::BeginGroup()
     group_data.BackupCurrLineSize = window->DC.CurrLineSize;
     group_data.BackupCurrLineTextBaseOffset = window->DC.CurrLineTextBaseOffset;
     group_data.BackupActiveIdIsAlive = g.ActiveIdIsAlive;
+    group_data.BackupHoveredIdIsAlive = g.HoveredId != 0;
     group_data.BackupActiveIdPreviousFrameIsAlive = g.ActiveIdPreviousFrameIsAlive;
     group_data.EmitItem = true;
 
@@ -8356,6 +8395,11 @@ void ImGui::EndGroup()
         window->DC.LastItemId = g.ActiveIdPreviousFrame;
     window->DC.LastItemRect = group_bb;
 
+    // Forward Hovered flag
+    const bool group_contains_curr_hovered_id = (group_data.BackupHoveredIdIsAlive == false) && g.HoveredId != 0;
+    if (group_contains_curr_hovered_id)
+        window->DC.LastItemStatusFlags |= ImGuiItemStatusFlags_HoveredWindow;
+
     // Forward Edited flag
     if (group_contains_curr_active_id && g.ActiveIdHasBeenEditedThisFrame)
         window->DC.LastItemStatusFlags |= ImGuiItemStatusFlags_Edited;
@@ -8765,12 +8809,12 @@ void ImGui::ClosePopupsOverWindow(ImGuiWindow* ref_window, bool restore_focus_to
             // Trim the stack unless the popup is a direct parent of the reference window (the reference window is often the NavWindow)
             // - With this stack of window, clicking/focusing Popup1 will close Popup2 and Popup3:
             //     Window -> Popup1 -> Popup2 -> Popup3
-            // - Each popups may contain child windows, which is why we compare ->RootWindow!
+            // - Each popups may contain child windows, which is why we compare ->RootWindowDockTree!
             //     Window -> Popup1 -> Popup1_Child -> Popup2 -> Popup2_Child
             bool ref_window_is_descendent_of_popup = false;
             for (int n = popup_count_to_keep; n < g.OpenPopupStack.Size; n++)
                 if (ImGuiWindow* popup_window = g.OpenPopupStack[n].Window)
-                    if (popup_window->RootWindow == ref_window->RootWindow)
+                    if (popup_window->RootWindowDockTree == ref_window->RootWindowDockTree)
                     {
                         ref_window_is_descendent_of_popup = true;
                         break;
@@ -9135,26 +9179,19 @@ ImVec2 ImGui::FindBestWindowPosForPopup(ImGuiWindow* window)
 // [SECTION] KEYBOARD/GAMEPAD NAVIGATION
 //-----------------------------------------------------------------------------
 
-// FIXME-NAV: The existence of SetNavID vs SetNavIDWithRectRel vs SetFocusID is incredibly messy and confusing,
-// and needs some explanation or serious refactoring.
-void ImGui::SetNavID(ImGuiID id, int nav_layer, ImGuiID focus_scope_id)
+// FIXME-NAV: The existence of SetNavID vs SetFocusID properly needs to be clarified/reworked.
+void ImGui::SetNavID(ImGuiID id, int nav_layer, ImGuiID focus_scope_id, const ImRect& rect_rel)
 {
     ImGuiContext& g = *GImGui;
-    IM_ASSERT(g.NavWindow);
-    IM_ASSERT(nav_layer == 0 || nav_layer == 1);
+    IM_ASSERT(g.NavWindow != NULL);
+    IM_ASSERT(nav_layer == ImGuiNavLayer_Main || nav_layer == ImGuiNavLayer_Menu);
     g.NavId = id;
+    g.NavLayer = (ImGuiNavLayer)nav_layer;
     g.NavFocusScopeId = focus_scope_id;
     g.NavWindow->NavLastIds[nav_layer] = id;
-}
-
-void ImGui::SetNavIDWithRectRel(ImGuiID id, int nav_layer, ImGuiID focus_scope_id, const ImRect& rect_rel)
-{
-    ImGuiContext& g = *GImGui;
-    SetNavID(id, nav_layer, focus_scope_id);
     g.NavWindow->NavRectRel[nav_layer] = rect_rel;
-    g.NavMousePosDirty = true;
-    g.NavDisableHighlight = false;
-    g.NavDisableMouseHover = true;
+    //g.NavDisableHighlight = false;
+    //g.NavDisableMouseHover = g.NavMousePosDirty = true;
 }
 
 void ImGui::SetFocusID(ImGuiID id, ImGuiWindow* window)
@@ -9453,7 +9490,7 @@ void ImGui::NavMoveRequestTryWrapping(ImGuiWindow* window, ImGuiNavMoveFlags mov
 static void ImGui::NavSaveLastChildNavWindowIntoParent(ImGuiWindow* nav_window)
 {
     ImGuiWindow* parent = nav_window;
-    while (parent && parent->RootWindowDockStop != parent && (parent->Flags & ImGuiWindowFlags_ChildWindow) != 0 && (parent->Flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_ChildMenu)) == 0)
+    while (parent && parent->RootWindow != parent && (parent->Flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_ChildMenu)) == 0)
         parent = parent->ParentWindow;
     if (parent && parent != nav_window)
         parent->NavLastChildNavWindow = nav_window;
@@ -9471,17 +9508,23 @@ static ImGuiWindow* ImGui::NavRestoreLastChildNavWindow(ImGuiWindow* window)
     return window;
 }
 
-static void NavRestoreLayer(ImGuiNavLayer layer)
+void ImGui::NavRestoreLayer(ImGuiNavLayer layer)
 {
     ImGuiContext& g = *GImGui;
-    g.NavLayer = layer;
-    if (layer == 0)
-        g.NavWindow = ImGui::NavRestoreLastChildNavWindow(g.NavWindow);
+    if (layer == ImGuiNavLayer_Main)
+        g.NavWindow = NavRestoreLastChildNavWindow(g.NavWindow);
     ImGuiWindow* window = g.NavWindow;
     if (window->NavLastIds[layer] != 0)
-        ImGui::SetNavIDWithRectRel(window->NavLastIds[layer], layer, 0, g.NavWindow->NavRectRel[layer]);
+    {
+        SetNavID(window->NavLastIds[layer], layer, 0, window->NavRectRel[layer]);
+        g.NavDisableHighlight = false;
+        g.NavDisableMouseHover = g.NavMousePosDirty = true;
+    }
     else
-        ImGui::NavInitWindow(window, true);
+    {
+        g.NavLayer = layer;
+        NavInitWindow(window, true);
+    }
 }
 
 static inline void ImGui::NavUpdateAnyRequestFlag()
@@ -9495,16 +9538,17 @@ static inline void ImGui::NavUpdateAnyRequestFlag()
 // This needs to be called before we submit any widget (aka in or before Begin)
 void ImGui::NavInitWindow(ImGuiWindow* window, bool force_reinit)
 {
+    // FIXME: ChildWindow test here is wrong for docking
     ImGuiContext& g = *GImGui;
     IM_ASSERT(window == g.NavWindow);
     bool init_for_nav = false;
     if (!(window->Flags & ImGuiWindowFlags_NoNavInputs))
-        if (!(window->Flags & ImGuiWindowFlags_ChildWindow) || (window->Flags & ImGuiWindowFlags_Popup) || (window->NavLastIds[0] == 0) || force_reinit)
+        if (window == window->RootWindow || (window->Flags & ImGuiWindowFlags_Popup) || (window->NavLastIds[0] == 0) || force_reinit)
             init_for_nav = true;
     IMGUI_DEBUG_LOG_NAV("[nav] NavInitRequest: from NavInitWindow(), init_for_nav=%d, window=\"%s\", layer=%d\n", init_for_nav, window->Name, g.NavLayer);
     if (init_for_nav)
     {
-        SetNavID(0, g.NavLayer, 0);
+        SetNavID(0, g.NavLayer, 0, ImRect());
         g.NavInitRequest = true;
         g.NavInitRequestFromMove = false;
         g.NavInitResultId = 0;
@@ -9592,17 +9636,17 @@ static void ImGui::NavUpdate()
     // (do it before we map Keyboard input!)
     bool nav_keyboard_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
     bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
-    if (nav_gamepad_active && g.NavInputSource != ImGuiInputSource_NavGamepad)
+    if (nav_gamepad_active && g.NavInputSource != ImGuiInputSource_Gamepad)
     {
         if (io.NavInputs[ImGuiNavInput_Activate] > 0.0f || io.NavInputs[ImGuiNavInput_Input] > 0.0f || io.NavInputs[ImGuiNavInput_Cancel] > 0.0f || io.NavInputs[ImGuiNavInput_Menu] > 0.0f
             || io.NavInputs[ImGuiNavInput_DpadLeft] > 0.0f || io.NavInputs[ImGuiNavInput_DpadRight] > 0.0f || io.NavInputs[ImGuiNavInput_DpadUp] > 0.0f || io.NavInputs[ImGuiNavInput_DpadDown] > 0.0f)
-            g.NavInputSource = ImGuiInputSource_NavGamepad;
+            g.NavInputSource = ImGuiInputSource_Gamepad;
     }
 
     // Update Keyboard->Nav inputs mapping
     if (nav_keyboard_active)
     {
-        #define NAV_MAP_KEY(_KEY, _NAV_INPUT)  do { if (IsKeyDown(io.KeyMap[_KEY])) { io.NavInputs[_NAV_INPUT] = 1.0f; g.NavInputSource = ImGuiInputSource_NavKeyboard; } } while (0)
+        #define NAV_MAP_KEY(_KEY, _NAV_INPUT)  do { if (IsKeyDown(io.KeyMap[_KEY])) { io.NavInputs[_NAV_INPUT] = 1.0f; g.NavInputSource = ImGuiInputSource_Keyboard; } } while (0)
         NAV_MAP_KEY(ImGuiKey_Space,     ImGuiNavInput_Activate );
         NAV_MAP_KEY(ImGuiKey_Enter,     ImGuiNavInput_Input    );
         NAV_MAP_KEY(ImGuiKey_Escape,    ImGuiNavInput_Cancel   );
@@ -9623,7 +9667,7 @@ static void ImGui::NavUpdate()
         io.NavInputsDownDuration[i] = (io.NavInputs[i] > 0.0f) ? (io.NavInputsDownDuration[i] < 0.0f ? 0.0f : io.NavInputsDownDuration[i] + io.DeltaTime) : -1.0f;
 
     // Process navigation init request (select first/default focus)
-    if (g.NavInitResultId != 0 && (!g.NavDisableHighlight || g.NavInitRequestFromMove))
+    if (g.NavInitResultId != 0)
         NavUpdateInitResult();
     g.NavInitRequest = false;
     g.NavInitRequestFromMove = false;
@@ -9648,13 +9692,11 @@ static void ImGui::NavUpdate()
     {
         // Set mouse position given our knowledge of the navigated item position from last frame
         if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableSetMousePos) && (io.BackendFlags & ImGuiBackendFlags_HasSetMousePos))
-        {
             if (!g.NavDisableHighlight && g.NavDisableMouseHover && g.NavWindow)
             {
                 io.MousePos = io.MousePosPrev = NavCalcPreferredRefPos();
                 io.WantSetMousePos = true;
             }
-        }
         g.NavMousePosDirty = false;
     }
     g.NavIdIsAlive = false;
@@ -9683,18 +9725,15 @@ static void ImGui::NavUpdate()
             if (!IsActiveIdUsingNavInput(ImGuiNavInput_Cancel))
                 ClearActiveID();
         }
-        else if (g.NavWindow && (g.NavWindow->Flags & ImGuiWindowFlags_ChildWindow) && !(g.NavWindow->Flags & ImGuiWindowFlags_Popup) && g.NavWindow->ParentWindow && g.NavWindow != g.NavWindow->RootWindowDockStop)
+        else if (g.NavWindow && g.NavWindow != g.NavWindow->RootWindow && !(g.NavWindow->Flags & ImGuiWindowFlags_Popup) && g.NavWindow->ParentWindow)
         {
             // Exit child window
             ImGuiWindow* child_window = g.NavWindow;
             ImGuiWindow* parent_window = g.NavWindow->ParentWindow;
             IM_ASSERT(child_window->ChildId != 0);
+            ImRect child_rect = child_window->Rect();
             FocusWindow(parent_window);
-            SetNavID(child_window->ChildId, 0, 0);
-            // Reassigning with same value, we're being explicit here.
-            g.NavIdIsAlive = false;     // -V1048
-            if (g.NavDisableMouseHover)
-                g.NavMousePosDirty = true;
+            SetNavID(child_window->ChildId, ImGuiNavLayer_Main, 0, ImRect(child_rect.Min - parent_window->Pos, child_rect.Max - parent_window->Pos));
         }
         else if (g.OpenPopupStack.Size > 0)
         {
@@ -9821,7 +9860,7 @@ static void ImGui::NavUpdate()
     // When using gamepad, we project the reference nav bounding box into window visible area.
     // This is to allow resuming navigation inside the visible area after doing a large amount of scrolling, since with gamepad every movements are relative
     // (can't focus a visible object like we can with the mouse).
-    if (g.NavMoveRequest && g.NavInputSource == ImGuiInputSource_NavGamepad && g.NavLayer == ImGuiNavLayer_Main)
+    if (g.NavMoveRequest && g.NavInputSource == ImGuiInputSource_Gamepad && g.NavLayer == ImGuiNavLayer_Main)
     {
         ImGuiWindow* window = g.NavWindow;
         ImRect window_rect_rel(window->InnerRect.Min - window->Pos - ImVec2(1, 1), window->InnerRect.Max - window->Pos + ImVec2(1, 1));
@@ -9863,11 +9902,12 @@ static void ImGui::NavUpdateInitResult()
 
     // Apply result from previous navigation init request (will typically select the first item, unless SetItemDefaultFocus() has been called)
     IMGUI_DEBUG_LOG_NAV("[nav] NavInitRequest: result NavID 0x%08X in Layer %d Window \"%s\"\n", g.NavInitResultId, g.NavLayer, g.NavWindow->Name);
+    SetNavID(g.NavInitResultId, g.NavLayer, 0, g.NavInitResultRectRel);
     if (g.NavInitRequestFromMove)
-        SetNavIDWithRectRel(g.NavInitResultId, g.NavLayer, 0, g.NavInitResultRectRel);
-    else
-        SetNavID(g.NavInitResultId, g.NavLayer, 0);
-    g.NavWindow->NavRectRel[g.NavLayer] = g.NavInitResultRectRel;
+    {
+        g.NavDisableHighlight = false;
+        g.NavDisableMouseHover = g.NavMousePosDirty = true;
+    }
 }
 
 // Apply result from previous frame navigation directional move request
@@ -9930,7 +9970,9 @@ static void ImGui::NavUpdateMoveResult()
         g.NavJustMovedToKeyMods = g.NavMoveRequestKeyMods;
     }
     IMGUI_DEBUG_LOG_NAV("[nav] NavMoveRequest: result NavID 0x%08X in Layer %d Window \"%s\"\n", result->ID, g.NavLayer, g.NavWindow->Name);
-    SetNavIDWithRectRel(result->ID, g.NavLayer, result->FocusScopeId, result->RectRel);
+    SetNavID(result->ID, g.NavLayer, result->FocusScopeId, result->RectRel);
+    g.NavDisableHighlight = false;
+    g.NavDisableMouseHover = g.NavMousePosDirty = true;
 }
 
 // Handle PageUp/PageDown/Home/End keys
@@ -10131,15 +10173,15 @@ static void ImGui::NavUpdateWindowing()
     if (start_windowing_with_gamepad || start_windowing_with_keyboard)
         if (ImGuiWindow* window = g.NavWindow ? g.NavWindow : FindWindowNavFocusable(g.WindowsFocusOrder.Size - 1, -INT_MAX, -1))
         {
-            g.NavWindowingTarget = g.NavWindowingTargetAnim = window->RootWindowDockStop;
+            g.NavWindowingTarget = g.NavWindowingTargetAnim = window->RootWindow;
             g.NavWindowingTimer = g.NavWindowingHighlightAlpha = 0.0f;
             g.NavWindowingToggleLayer = start_windowing_with_keyboard ? false : true;
-            g.NavInputSource = start_windowing_with_keyboard ? ImGuiInputSource_NavKeyboard : ImGuiInputSource_NavGamepad;
+            g.NavInputSource = start_windowing_with_keyboard ? ImGuiInputSource_Keyboard : ImGuiInputSource_Gamepad;
         }
 
     // Gamepad update
     g.NavWindowingTimer += g.IO.DeltaTime;
-    if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_NavGamepad)
+    if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_Gamepad)
     {
         // Highlight only appears after a brief time holding the button, so that a fast tap on PadMenu (to toggle NavLayer) doesn't add visual noise
         g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha, ImSaturate((g.NavWindowingTimer - NAV_WINDOWING_HIGHLIGHT_DELAY) / 0.05f));
@@ -10165,7 +10207,7 @@ static void ImGui::NavUpdateWindowing()
     }
 
     // Keyboard: Focus
-    if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_NavKeyboard)
+    if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_Keyboard)
     {
         // Visuals only appears after a brief time after pressing TAB the first time, so that a fast CTRL+TAB doesn't add visual noise
         g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha, ImSaturate((g.NavWindowingTimer - NAV_WINDOWING_HIGHLIGHT_DELAY) / 0.05f)); // 1.0f
@@ -10187,15 +10229,15 @@ static void ImGui::NavUpdateWindowing()
     if (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoMove))
     {
         ImVec2 move_delta;
-        if (g.NavInputSource == ImGuiInputSource_NavKeyboard && !g.IO.KeyShift)
+        if (g.NavInputSource == ImGuiInputSource_Keyboard && !g.IO.KeyShift)
             move_delta = GetNavInputAmount2d(ImGuiNavDirSourceFlags_Keyboard, ImGuiInputReadMode_Down);
-        if (g.NavInputSource == ImGuiInputSource_NavGamepad)
+        if (g.NavInputSource == ImGuiInputSource_Gamepad)
             move_delta = GetNavInputAmount2d(ImGuiNavDirSourceFlags_PadLStick, ImGuiInputReadMode_Down);
         if (move_delta.x != 0.0f || move_delta.y != 0.0f)
         {
             const float NAV_MOVE_SPEED = 800.0f;
             const float move_speed = ImFloor(NAV_MOVE_SPEED * g.IO.DeltaTime * ImMin(g.IO.DisplayFramebufferScale.x, g.IO.DisplayFramebufferScale.y)); // FIXME: Doesn't handle variable framerate very well
-            ImGuiWindow* moving_window = g.NavWindowingTarget->RootWindow;
+            ImGuiWindow* moving_window = g.NavWindowingTarget->RootWindowDockTree;
             SetWindowPos(moving_window, moving_window->Pos + move_delta * move_speed, ImGuiCond_Always);
             MarkIniSettingsDirty(moving_window);
             g.NavDisableMouseHover = true;
@@ -10203,7 +10245,7 @@ static void ImGui::NavUpdateWindowing()
     }
 
     // Apply final focus
-    if (apply_focus_window && (g.NavWindow == NULL || apply_focus_window != g.NavWindow->RootWindowDockStop))
+    if (apply_focus_window && (g.NavWindow == NULL || apply_focus_window != g.NavWindow->RootWindow))
     {
         ImGuiViewport* previous_viewport = g.NavWindow ? g.NavWindow->Viewport : NULL;
         ClearActiveID();
@@ -10245,11 +10287,11 @@ static void ImGui::NavUpdateWindowing()
         g.NavDisableHighlight = false;
         g.NavDisableMouseHover = true;
 
-        // When entering a regular menu bar with the Alt key, we always reinitialize the navigation ID. It however persist on docking tab tabs.
+        // Reinitialize navigation when entering menu bar with the Alt key. We make it persist on Docking Tab Bars.
         const ImGuiNavLayer new_nav_layer = (g.NavWindow->DC.NavLayerActiveMask & (1 << ImGuiNavLayer_Menu)) ? (ImGuiNavLayer)((int)g.NavLayer ^ 1) : ImGuiNavLayer_Main;
         const bool preserve_layer_1_nav_id = (new_nav_window->DockNodeAsHost != NULL);
         if (new_nav_layer == ImGuiNavLayer_Menu && !preserve_layer_1_nav_id)
-            g.NavWindow->NavLastIds[ImGuiNavLayer_Menu] = 0;
+            g.NavWindow->NavLastIds[new_nav_layer] = 0;
         NavRestoreLayer(new_nav_layer);
     }
 }
@@ -10315,27 +10357,45 @@ void ImGui::ClearDragDrop()
     memset(&g.DragDropPayloadBufLocal, 0, sizeof(g.DragDropPayloadBufLocal));
 }
 
-// Call when current ID is active.
 // When this returns true you need to: a) call SetDragDropPayload() exactly once, b) you may render the payload visual/description, c) call EndDragDropSource()
+// If the item has an identifier:
+// - This assume/require the item to be activated (typically via ButtonBehavior).
+// - Therefore if you want to use this with a mouse button other than left mouse button, it is up to the item itself to activate with another button.
+// - We then pull and use the mouse button that was used to activate the item and use it to carry on the drag.
+// If the item has no identifier:
+// - Currently always assume left mouse button.
 bool ImGui::BeginDragDropSource(ImGuiDragDropFlags flags)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
 
+    // FIXME-DRAGDROP: While in the common-most "drag from non-zero active id" case we can tell the mouse button,
+    // in both SourceExtern and id==0 cases we may requires something else (explicit flags or some heuristic).
+    ImGuiMouseButton mouse_button = ImGuiMouseButton_Left;
+
     bool source_drag_active = false;
     ImGuiID source_id = 0;
     ImGuiID source_parent_id = 0;
-    ImGuiMouseButton mouse_button = ImGuiMouseButton_Left;
     if (!(flags & ImGuiDragDropFlags_SourceExtern))
     {
         source_id = window->DC.LastItemId;
-        if (source_id != 0 && g.ActiveId != source_id) // Early out for most common case
-            return false;
-        if (g.IO.MouseDown[mouse_button] == false)
-            return false;
-
-        if (source_id == 0)
+        if (source_id != 0)
+        {
+            // Common path: items with ID
+            if (g.ActiveId != source_id)
+                return false;
+            if (g.ActiveIdMouseButton != -1)
+                mouse_button = g.ActiveIdMouseButton;
+            if (g.IO.MouseDown[mouse_button] == false)
+                return false;
+            g.ActiveIdAllowOverlap = false;
+        }
+        else
         {
+            // Uncommon path: items without ID
+            if (g.IO.MouseDown[mouse_button] == false)
+                return false;
+
             // If you want to use BeginDragDropSource() on an item with no unique identifier for interaction, such as Text() or Image(), you need to:
             // A) Read the explanation below, B) Use the ImGuiDragDropFlags_SourceAllowNullID flag, C) Swallow your programmer pride.
             if (!(flags & ImGuiDragDropFlags_SourceAllowNullID))
@@ -10362,10 +10422,6 @@ bool ImGui::BeginDragDropSource(ImGuiDragDropFlags flags)
             if (g.ActiveId == source_id) // Allow the underlying widget to display/return hovered during the mouse release frame, else we would get a flicker.
                 g.ActiveIdAllowOverlap = is_hovered;
         }
-        else
-        {
-            g.ActiveIdAllowOverlap = false;
-        }
         if (g.ActiveId != source_id)
             return false;
         source_parent_id = window->IDStack.back();
@@ -10489,7 +10545,7 @@ bool ImGui::BeginDragDropTargetCustom(const ImRect& bb, ImGuiID id)
 
     ImGuiWindow* window = g.CurrentWindow;
     ImGuiWindow* hovered_window = g.HoveredWindowUnderMovingWindow;
-    if (hovered_window == NULL || window->RootWindow != hovered_window->RootWindow)
+    if (hovered_window == NULL || window->RootWindowDockTree != hovered_window->RootWindowDockTree)
         return false;
     IM_ASSERT(id != 0);
     if (!IsMouseHoveringRect(bb.Min, bb.Max) || (id == g.DragDropPayload.SourceId))
@@ -10518,7 +10574,7 @@ bool ImGui::BeginDragDropTarget()
     if (!(window->DC.LastItemStatusFlags & ImGuiItemStatusFlags_HoveredRect))
         return false;
     ImGuiWindow* hovered_window = g.HoveredWindowUnderMovingWindow;
-    if (hovered_window == NULL || window->RootWindow != hovered_window->RootWindow)
+    if (hovered_window == NULL || window->RootWindowDockTree != hovered_window->RootWindowDockTree)
         return false;
 
     const ImRect& display_rect = (window->DC.LastItemStatusFlags & ImGuiItemStatusFlags_HasDisplayRect) ? window->DC.LastItemDisplayRect : window->DC.LastItemRect;
@@ -10568,11 +10624,11 @@ const ImGuiPayload* ImGui::AcceptDragDropPayload(const char* type, ImGuiDragDrop
     flags |= (g.DragDropSourceFlags & ImGuiDragDropFlags_AcceptNoDrawDefaultRect); // Source can also inhibit the preview (useful for external sources that lives for 1 frame)
     if (!(flags & ImGuiDragDropFlags_AcceptNoDrawDefaultRect) && payload.Preview)
     {
-        // FIXME-DRAG: Settle on a proper default visuals for drop target.
+        // FIXME-DRAGDROP: Settle on a proper default visuals for drop target.
         r.Expand(3.5f);
         bool push_clip_rect = !window->ClipRect.Contains(r);
         if (push_clip_rect) window->DrawList->PushClipRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1));
-        window->DrawList->AddRect(r.Min, r.Max, GetColorU32(ImGuiCol_DragDropTarget), 0.0f, ~0, 2.0f);
+        window->DrawList->AddRect(r.Min, r.Max, GetColorU32(ImGuiCol_DragDropTarget), 0.0f, 0, 2.0f);
         if (push_clip_rect) window->DrawList->PopClipRect();
     }
 
@@ -10607,14 +10663,8 @@ void ImGui::EndDragDropTarget()
 //-----------------------------------------------------------------------------
 
 // Pass text data straight to log (without being displayed)
-void ImGui::LogText(const char* fmt, ...)
+static inline void LogTextV(ImGuiContext& g, const char* fmt, va_list args)
 {
-    ImGuiContext& g = *GImGui;
-    if (!g.LogEnabled)
-        return;
-
-    va_list args;
-    va_start(args, fmt);
     if (g.LogFile)
     {
         g.LogBuffer.Buf.resize(0);
@@ -10625,9 +10675,29 @@ void ImGui::LogText(const char* fmt, ...)
     {
         g.LogBuffer.appendfv(fmt, args);
     }
+}
+
+void ImGui::LogText(const char* fmt, ...)
+{
+    ImGuiContext& g = *GImGui;
+    if (!g.LogEnabled)
+        return;
+
+    va_list args;
+    va_start(args, fmt);
+    LogTextV(g, fmt, args);
     va_end(args);
 }
 
+void ImGui::LogTextV(const char* fmt, va_list args)
+{
+    ImGuiContext& g = *GImGui;
+    if (!g.LogEnabled)
+        return;
+
+    LogTextV(g, fmt, args);
+}
+
 // Internal version that takes a position to decide on newline placement and pad items according to their depth.
 // We split text into individual lines to add current tree level padding
 // FIXME: This code is a little complicated perhaps, considering simplifying the whole system.
@@ -11157,7 +11227,6 @@ static void WindowSettingsHandler_WriteAll(ImGuiContext* ctx, ImGuiSettingsHandl
         buf->appendf("Collapsed=%d\n", settings->Collapsed);
         if (settings->DockId != 0)
         {
-            // Write DockId as 4 digits if possible. Automatic DockId are small numbers, but full explicit DockSpace() are full ImGuiID range.
             if (settings->DockOrder == -1)
                 buf->appendf("DockId=0x%08X\n", settings->DockId);
             else
@@ -11485,6 +11554,17 @@ static void ImGui::UpdateViewportsNewFrame()
         viewport->DpiScale = new_dpi_scale;
     }
 
+    // Update fallback monitor
+    if (g.PlatformIO.Monitors.Size == 0)
+    {
+        ImGuiPlatformMonitor* monitor = &g.FallbackMonitor;
+        monitor->MainPos = main_viewport->Pos;
+        monitor->MainSize = main_viewport->Size;
+        monitor->WorkPos = main_viewport->WorkPos;
+        monitor->WorkSize = main_viewport->WorkSize;
+        monitor->DpiScale = main_viewport->DpiScale;
+    }
+
     if (!viewports_enabled)
     {
         g.MouseViewport = main_viewport;
@@ -11567,7 +11647,7 @@ ImGuiViewportP* ImGui::AddUpdateViewport(ImGuiWindow* window, ImGuiID id, const
     flags |= ImGuiViewportFlags_IsPlatformWindow;
     if (window != NULL)
     {
-        if (g.MovingWindow && g.MovingWindow->RootWindow == window)
+        if (g.MovingWindow && g.MovingWindow->RootWindowDockTree == window)
             flags |= ImGuiViewportFlags_NoInputs | ImGuiViewportFlags_NoFocusOnAppearing;
         if ((window->Flags & ImGuiWindowFlags_NoMouseInputs) && (window->Flags & ImGuiWindowFlags_NoNavInputs))
             flags |= ImGuiViewportFlags_NoInputs;
@@ -11680,7 +11760,7 @@ static void ImGui::UpdateSelectWindowViewport(ImGuiWindow* window)
     {
         window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_None);
     }
-    else if (g.MovingWindow && g.MovingWindow->RootWindow == window && IsMousePosValid())
+    else if (g.MovingWindow && g.MovingWindow->RootWindowDockTree == window && IsMousePosValid())
     {
         if (window->Viewport != NULL && window->Viewport->Window == window)
             window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_None);
@@ -11698,7 +11778,7 @@ static void ImGui::UpdateSelectWindowViewport(ImGuiWindow* window)
     if (window->Viewport == NULL)
         if (!UpdateTryMergeWindowIntoHostViewport(window, main_viewport))
             window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_None);
-    
+
     // Mark window as allowed to protrude outside of its viewport and into the current monitor
     if (!lock_viewport)
     {
@@ -11961,6 +12041,17 @@ static void ImGui::UpdateViewportPlatformMonitor(ImGuiViewportP* viewport)
     viewport->PlatformMonitor = (short)FindPlatformMonitorForRect(viewport->GetMainRect());
 }
 
+// Return value is always != NULL, but don't hold on it across frames.
+const ImGuiPlatformMonitor* ImGui::GetViewportPlatformMonitor(ImGuiViewport* viewport_p)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiViewportP* viewport = (ImGuiViewportP*)(void*)viewport_p;
+    int monitor_idx = viewport->PlatformMonitor;
+    if (monitor_idx >= 0 || monitor_idx < g.PlatformIO.Monitors.Size)
+        return &g.PlatformIO.Monitors[monitor_idx];
+    return &g.FallbackMonitor;
+}
+
 void ImGui::DestroyPlatformWindow(ImGuiViewportP* viewport)
 {
     ImGuiContext& g = *GImGui;
@@ -12120,14 +12211,14 @@ struct ImGuiDockNodeSettings
     ImGuiID             ID;
     ImGuiID             ParentNodeId;
     ImGuiID             ParentWindowId;
-    ImGuiID             SelectedWindowId;
+    ImGuiID             SelectedTabId;
     signed char         SplitAxis;
     char                Depth;
     ImGuiDockNodeFlags  Flags;                  // NB: We save individual flags one by one in ascii format (ImGuiDockNodeFlags_SavedFlagsMask_)
     ImVec2ih            Pos;
     ImVec2ih            Size;
     ImVec2ih            SizeRef;
-    ImGuiDockNodeSettings() { ID = ParentNodeId = ParentWindowId = SelectedWindowId = 0; SplitAxis = ImGuiAxis_None; Depth = 0; Flags = ImGuiDockNodeFlags_None; }
+    ImGuiDockNodeSettings() { memset(this, 0, sizeof(*this)); SplitAxis = ImGuiAxis_None; }
 };
 
 //-----------------------------------------------------------------------------
@@ -12327,8 +12418,8 @@ void ImGui::DockContextNewFrameUpdateDocking(ImGuiContext* ctx)
     {
         if (hovered_window->DockNodeAsHost)
             g.HoveredDockNode = DockNodeTreeFindVisibleNodeByPos(hovered_window->DockNodeAsHost, g.IO.MousePos);
-        else if (hovered_window->RootWindowDockStop->DockNode)
-            g.HoveredDockNode = hovered_window->RootWindowDockStop->DockNode;
+        else if (hovered_window->RootWindow->DockNode)
+            g.HoveredDockNode = hovered_window->RootWindow->DockNode;
     }
 
     // Process Docking requests
@@ -12504,7 +12595,7 @@ static void ImGui::DockContextBuildNodesFromSettings(ImGuiContext* ctx, ImGuiDoc
             node->ParentNode->ChildNodes[0] = node;
         else if (node->ParentNode && node->ParentNode->ChildNodes[1] == NULL)
             node->ParentNode->ChildNodes[1] = node;
-        node->SelectedTabId = settings->SelectedWindowId;
+        node->SelectedTabId = settings->SelectedTabId;
         node->SplitAxis = (ImGuiAxis)settings->SplitAxis;
         node->LocalFlags |= (settings->Flags & ImGuiDockNodeFlags_SavedFlagsMask_);
 
@@ -12838,7 +12929,7 @@ ImGuiDockNode::ImGuiDockNode(ImGuiID id)
     AuthorityForPos = AuthorityForSize = ImGuiDataAuthority_DockNode;
     AuthorityForViewport = ImGuiDataAuthority_Auto;
     IsVisible = true;
-    IsFocused = HasCloseButton = HasWindowMenuButton = EnableCloseButton = false;
+    IsFocused = HasCloseButton = HasWindowMenuButton = false;
     WantCloseAll = WantLockSizeOnce = WantMouseMove = WantHiddenTabBarUpdate = WantHiddenTabBarToggle = false;
     MarkedForPosSizeWrite = false;
 }
@@ -12924,7 +13015,7 @@ static void ImGui::DockNodeRemoveWindow(ImGuiDockNode* node, ImGuiWindow* window
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(window->DockNode == node);
-    //IM_ASSERT(window->RootWindow == node->HostWindow);
+    //IM_ASSERT(window->RootWindowDockTree == node->HostWindow);
     //IM_ASSERT(window->LastFrameActive < g.FrameCount);    // We may call this from Begin()
     IM_ASSERT(save_dock_id == 0 || save_dock_id == node->ID);
     IMGUI_DEBUG_LOG_DOCKING("DockNodeRemoveWindow node 0x%08X window '%s'\n", node->ID, window->Name);
@@ -13148,6 +13239,7 @@ static void ImGui::DockNodeUpdateVisibleFlagAndInactiveChilds(ImGuiDockNode* nod
         }
         else
         {
+            // FIXME-DOCKING: Missing policies for conflict resolution, hence the "Experimental" tag on this.
             node->LocalFlags &= ~window->WindowClass.DockNodeFlagsOverrideClear;
             node->LocalFlags |= window->WindowClass.DockNodeFlagsOverrideSet;
         }
@@ -13272,7 +13364,7 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
         node->State = ImGuiDockNodeState_HostWindowHiddenBecauseSingleWindow;
         node->WantCloseAll = false;
         node->WantCloseTabId = 0;
-        node->HasCloseButton = node->HasWindowMenuButton = node->EnableCloseButton = false;
+        node->HasCloseButton = node->HasWindowMenuButton = false;
         node->LastFrameActive = g.FrameCount;
 
         if (node->WantMouseMove && node->Windows.Size == 1)
@@ -13307,6 +13399,19 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
 
     const ImGuiDockNodeFlags node_flags = node->GetMergedFlags();
 
+    // Decide if the node will have a close button and a window menu button
+    node->HasWindowMenuButton = (node->Windows.Size > 0) && (node_flags & ImGuiDockNodeFlags_NoWindowMenuButton) == 0;
+    node->HasCloseButton = false;
+    for (int window_n = 0; window_n < node->Windows.Size; window_n++)
+    {
+        // FIXME-DOCK: Setting DockIsActive here means that for single active window in a leaf node, DockIsActive will be cleared until the next Begin() call.
+        ImGuiWindow* window = node->Windows[window_n];
+        node->HasCloseButton |= window->HasCloseButton;
+        window->DockIsActive = (node->Windows.Size > 1);
+    }
+    if (node_flags & ImGuiDockNodeFlags_NoCloseButton)
+        node->HasCloseButton = false;
+
     // Bind or create host window
     ImGuiWindow* host_window = NULL;
     bool beginned_into_host_window = false;
@@ -13314,25 +13419,11 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
     {
         // [Explicit root dockspace node]
         IM_ASSERT(node->HostWindow);
-        node->EnableCloseButton = false;
-        node->HasCloseButton = (node_flags & ImGuiDockNodeFlags_NoCloseButton) == 0;
-        node->HasWindowMenuButton = (node_flags & ImGuiDockNodeFlags_NoWindowMenuButton) == 0;
         host_window = node->HostWindow;
     }
     else
     {
         // [Automatic root or child nodes]
-        node->EnableCloseButton = false;
-        node->HasCloseButton = (node->Windows.Size > 0) && (node_flags & ImGuiDockNodeFlags_NoCloseButton) == 0;
-        node->HasWindowMenuButton = (node->Windows.Size > 0) && (node_flags & ImGuiDockNodeFlags_NoWindowMenuButton) == 0;
-        for (int window_n = 0; window_n < node->Windows.Size; window_n++)
-        {
-            // FIXME-DOCK: Setting DockIsActive here means that for single active window in a leaf node, DockIsActive will be cleared until the next Begin() call.
-            ImGuiWindow* window = node->Windows[window_n];
-            window->DockIsActive = (node->Windows.Size > 1);
-            node->EnableCloseButton |= window->HasCloseButton;
-        }
-
         if (node->IsRootNode() && node->IsVisible)
         {
             ImGuiWindow* ref_window = (node->Windows.Size > 0) ? node->Windows[0] : NULL;
@@ -13402,8 +13493,8 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
     if (node->IsSplitNode())
         IM_ASSERT(node->TabBar == NULL);
     if (node->IsRootNode())
-        if (g.NavWindow && g.NavWindow->RootWindowDockStop->DockNode && g.NavWindow->RootWindowDockStop->ParentWindow == host_window)
-            node->LastFocusedNodeId = g.NavWindow->RootWindowDockStop->DockNode->ID;
+        if (g.NavWindow && g.NavWindow->RootWindow->DockNode && g.NavWindow->RootWindow->ParentWindow == host_window)
+            node->LastFocusedNodeId = g.NavWindow->RootWindow->DockNode->ID;
 
     // We need to draw a background at the root level if requested by ImGuiDockNodeFlags_PassthruCentralNode, but we will only know the correct pos/size
     // _after_ processing the resizing splitters. So we are using the DrawList channel splitting facility to submit drawing primitives out of order!
@@ -13483,7 +13574,7 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
 
     // Draw payload drop target
     if (host_window && node->IsVisible)
-        if (node->IsRootNode() && (g.MovingWindow == NULL || g.MovingWindow->RootWindow != host_window))
+        if (node->IsRootNode() && (g.MovingWindow == NULL || g.MovingWindow->RootWindowDockTree != host_window))
             BeginDockableDragDropTarget(host_window);
 
     // We update this after DockNodeUpdateTabBar()
@@ -13564,7 +13655,7 @@ bool ImGui::DockNodeBeginAmendTabBar(ImGuiDockNode* node)
     PushOverrideID(node->ID);
     bool ret = BeginTabBarEx(node->TabBar, node->TabBar->BarRect, node->TabBar->Flags, node);
     IM_UNUSED(ret);
-    IM_ASSERT(ret);    
+    IM_ASSERT(ret);
     return true;
 }
 
@@ -13592,7 +13683,7 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
     ImGuiDockNode* root_node = DockNodeGetRootNode(node);
     if (g.NavWindowingTarget)
         is_focused = (g.NavWindowingTarget->DockNode == node);
-    else if (g.NavWindow && g.NavWindow->RootWindowForTitleBarHighlight == host_window->RootWindow && root_node->LastFocusedNodeId == node->ID)
+    else if (g.NavWindow && g.NavWindow->RootWindowForTitleBarHighlight == host_window->RootWindowDockTree && root_node->LastFocusedNodeId == node->ID)
         is_focused = true;
 
     // Hidden tab bar will show a triangle on the upper-left (in Begin)
@@ -13638,7 +13729,6 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
 
     const ImGuiDockNodeFlags node_flags = node->GetMergedFlags();
     const bool has_window_menu_button = (node_flags & ImGuiDockNodeFlags_NoWindowMenuButton) == 0 && (style.WindowMenuButtonPosition != ImGuiDir_None);
-    const bool has_close_button = (node_flags & ImGuiDockNodeFlags_NoCloseButton) == 0;
 
     // In a dock node, the Collapse Button turns into the Window Menu button.
     // FIXME-DOCK FIXME-OPT: Could we recycle popups id across multiple dock nodes?
@@ -13659,7 +13749,7 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
     for (int window_n = 0; window_n < node->Windows.Size; window_n++)
     {
         ImGuiWindow* window = node->Windows[window_n];
-        if (g.NavWindow && g.NavWindow->RootWindowDockStop == window)
+        if (g.NavWindow && g.NavWindow->RootWindow == window)
             tab_bar->SelectedTabId = window->ID;
         if (TabBarFindTabByID(tab_bar, window->ID) == NULL)
             TabBarAddTab(tab_bar, ImGuiTabItemFlags_Unsorted, window);
@@ -13669,7 +13759,7 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
     if (is_focused)
         node->LastFrameFocused = g.FrameCount;
     ImU32 title_bar_col = GetColorU32(host_window->Collapsed ? ImGuiCol_TitleBgCollapsed : is_focused ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg);
-    host_window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, host_window->WindowRounding, ImDrawCornerFlags_Top);
+    host_window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, host_window->WindowRounding, ImDrawFlags_RoundCornersTop);
 
     // Docking/Collapse button
     if (has_window_menu_button)
@@ -13748,7 +13838,7 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
             window->DockTabItemRect = host_window->DC.LastItemRect;
 
             // Update navigation ID on menu layer
-            if (g.NavWindow && g.NavWindow->RootWindowDockStop == window && (window->DC.NavLayerActiveMask & (1 << ImGuiNavLayer_Menu)) == 0)
+            if (g.NavWindow && g.NavWindow->RootWindow == window && (window->DC.NavLayerActiveMask & (1 << ImGuiNavLayer_Menu)) == 0)
                 host_window->NavLastIds[1] = window->ID;
         }
     }
@@ -13764,12 +13854,15 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
 
     // Close button (after VisibleWindow was updated)
     // Note that VisibleWindow may have been overrided by CTRL+Tabbing, so VisibleWindow->ID may be != from tab_bar->SelectedTabId
-    if (has_close_button && node->VisibleWindow)
+    const bool close_button_is_enabled = node->HasCloseButton && node->VisibleWindow && node->VisibleWindow->HasCloseButton;
+    const bool close_button_is_visible = node->HasCloseButton;
+    //const bool close_button_is_visible = close_button_is_enabled; // Most people would expect this behavior of not even showing the button (leaving a hole since we can't claim that space as other windows in the tba bar have one)
+    if (close_button_is_visible)
     {
-        if (!node->VisibleWindow->HasCloseButton)
+        if (!close_button_is_enabled)
         {
             PushItemFlag(ImGuiItemFlags_Disabled, true);
-            PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_Text] * ImVec4(1.0f,1.0f,1.0f,0.5f));
+            PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_Text] * ImVec4(1.0f,1.0f,1.0f,0.4f));
         }
         const float button_sz = g.FontSize;
         if (CloseButton(host_window->GetID("#CLOSE"), title_bar_rect.GetTR() + ImVec2(-style.FramePadding.x * 2.0f - button_sz, 0.0f)))
@@ -13780,7 +13873,7 @@ static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_w
             }
         //if (IsItemActive())
         //    focus_tab_id = tab_bar->SelectedTabId;
-        if (!node->VisibleWindow->HasCloseButton)
+        if (!close_button_is_enabled)
         {
             PopStyleColor();
             PopItemFlag();
@@ -15337,7 +15430,7 @@ void ImGui::BeginDockableDragDropSource(ImGuiWindow* window)
     IM_ASSERT(g.MovingWindow == window);
 
     window->DC.LastItemId = window->MoveId;
-    window = window->RootWindow;
+    window = window->RootWindowDockTree;
     IM_ASSERT((window->Flags & ImGuiWindowFlags_NoDocking) == 0);
     bool is_drag_docking = (g.IO.ConfigDockingWithShift) || ImRect(0, 0, window->SizeFull.x, GetFrameHeight()).Contains(g.ActiveIdClickOffset);
     if (is_drag_docking && BeginDragDropSource(ImGuiDragDropFlags_SourceNoPreviewTooltip | ImGuiDragDropFlags_SourceNoHoldToOpenOthers | ImGuiDragDropFlags_SourceAutoExpirePayload))
@@ -15356,7 +15449,7 @@ void ImGui::BeginDockableDragDropTarget(ImGuiWindow* window)
     ImGuiContext* ctx = GImGui;
     ImGuiContext& g = *ctx;
 
-    //IM_ASSERT(window->RootWindow == window); // May also be a DockSpace
+    //IM_ASSERT(window->RootWindowDockTree == window); // May also be a DockSpace
     IM_ASSERT((window->Flags & ImGuiWindowFlags_NoDocking) == 0);
     if (!g.DragDropActive)
         return;
@@ -15550,7 +15643,7 @@ static void ImGui::DockSettingsHandler_ReadLine(ImGuiContext* ctx, ImGuiSettings
     if (sscanf(line, " HiddenTabBar=%d%n", &x, &r) == 1)            { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_HiddenTabBar; }
     if (sscanf(line, " NoWindowMenuButton=%d%n", &x, &r) == 1)      { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_NoWindowMenuButton; }
     if (sscanf(line, " NoCloseButton=%d%n", &x, &r) == 1)           { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_NoCloseButton; }
-    if (sscanf(line, " Selected=0x%08X%n", &node.SelectedWindowId,&r) == 1) { line += r; }
+    if (sscanf(line, " Selected=0x%08X%n", &node.SelectedTabId,&r) == 1) { line += r; }
     if (node.ParentNodeId != 0)
         if (ImGuiDockNodeSettings* parent_settings = DockSettingsFindNodeSettings(ctx, node.ParentNodeId))
             node.Depth = parent_settings->Depth + 1;
@@ -15564,7 +15657,7 @@ static void DockSettingsHandler_DockNodeToSettings(ImGuiDockContext* dc, ImGuiDo
     node_settings.ID = node->ID;
     node_settings.ParentNodeId = node->ParentNode ? node->ParentNode->ID : 0;
     node_settings.ParentWindowId = (node->IsDockSpace() && node->HostWindow && node->HostWindow->ParentWindow) ? node->HostWindow->ParentWindow->ID : 0;
-    node_settings.SelectedWindowId = node->SelectedTabId;
+    node_settings.SelectedTabId = node->SelectedTabId;
     node_settings.SplitAxis = (signed char)(node->IsSplitNode() ? node->SplitAxis : ImGuiAxis_None);
     node_settings.Depth = (char)depth;
     node_settings.Flags = (node->LocalFlags & ImGuiDockNodeFlags_SavedFlagsMask_);
@@ -15630,8 +15723,8 @@ static void ImGui::DockSettingsHandler_WriteAll(ImGuiContext* ctx, ImGuiSettings
             buf->appendf(" NoWindowMenuButton=1");
         if (node_settings->Flags & ImGuiDockNodeFlags_NoCloseButton)
             buf->appendf(" NoCloseButton=1");
-        if (node_settings->SelectedWindowId)
-            buf->appendf(" Selected=0x%08X", node_settings->SelectedWindowId);
+        if (node_settings->SelectedTabId)
+            buf->appendf(" Selected=0x%08X", node_settings->SelectedTabId);
 
 #if IMGUI_DEBUG_INI_SETTINGS
         // [DEBUG] Include comments in the .ini file to ease debugging
@@ -15992,7 +16085,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
 
                 BulletText("Table 0x%08X (%d columns, in '%s')", table->ID, table->ColumnsCount, table->OuterWindow->Name);
                 if (IsItemHovered())
-                    GetForegroundDrawList()->AddRect(table->OuterRect.Min - ImVec2(1, 1), table->OuterRect.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, ~0, 2.0f);
+                    GetForegroundDrawList()->AddRect(table->OuterRect.Min - ImVec2(1, 1), table->OuterRect.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, 0, 2.0f);
                 Indent();
                 char buf[128];
                 for (int rect_n = 0; rect_n < TRT_Count; rect_n++)
@@ -16007,7 +16100,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
                             ImFormatString(buf, IM_ARRAYSIZE(buf), "(%6.1f,%6.1f) (%6.1f,%6.1f) Size (%6.1f,%6.1f) Col %d %s", r.Min.x, r.Min.y, r.Max.x, r.Max.y, r.GetWidth(), r.GetHeight(), column_n, trt_rects_names[rect_n]);
                             Selectable(buf);
                             if (IsItemHovered())
-                                GetForegroundDrawList()->AddRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, ~0, 2.0f);
+                                GetForegroundDrawList()->AddRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, 0, 2.0f);
                         }
                     }
                     else
@@ -16016,7 +16109,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
                         ImFormatString(buf, IM_ARRAYSIZE(buf), "(%6.1f,%6.1f) (%6.1f,%6.1f) Size (%6.1f,%6.1f) %s", r.Min.x, r.Min.y, r.Max.x, r.Max.y, r.GetWidth(), r.GetHeight(), trt_rects_names[rect_n]);
                         Selectable(buf);
                         if (IsItemHovered())
-                            GetForegroundDrawList()->AddRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, ~0, 2.0f);
+                            GetForegroundDrawList()->AddRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, 0, 2.0f);
                     }
                 }
                 Unindent();
@@ -16192,14 +16285,14 @@ void ImGui::ShowMetricsWindow(bool* p_open)
             {
                 ImGuiDockNodeSettings* settings = &dc->NodesSettings[n];
                 const char* selected_tab_name = NULL;
-                if (settings->SelectedWindowId)
+                if (settings->SelectedTabId)
                 {
-                    if (ImGuiWindow* window = FindWindowByID(settings->SelectedWindowId))
+                    if (ImGuiWindow* window = FindWindowByID(settings->SelectedTabId))
                         selected_tab_name = window->Name;
-                    else if (ImGuiWindowSettings* window_settings = FindWindowSettings(settings->SelectedWindowId))
+                    else if (ImGuiWindowSettings* window_settings = FindWindowSettings(settings->SelectedTabId))
                         selected_tab_name = window_settings->GetName();
                 }
-                BulletText("Node %08X, Parent %08X, SelectedTab %08X ('%s')", settings->ID, settings->ParentNodeId, settings->SelectedWindowId, selected_tab_name ? selected_tab_name : settings->SelectedWindowId ? "N/A" : "");
+                BulletText("Node %08X, Parent %08X, SelectedTab %08X ('%s')", settings->ID, settings->ParentNodeId, settings->SelectedTabId, selected_tab_name ? selected_tab_name : settings->SelectedTabId ? "N/A" : "");
             }
             TreePop();
         }
@@ -16221,7 +16314,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
         Text("WINDOWING");
         Indent();
         Text("HoveredWindow: '%s'", g.HoveredWindow ? g.HoveredWindow->Name : "NULL");
-        Text("HoveredRootWindow: '%s'", g.HoveredRootWindow ? g.HoveredRootWindow->Name : "NULL");
+        Text("HoveredWindow->Root: '%s'", g.HoveredWindow ? g.HoveredWindow->RootWindowDockTree->Name : "NULL");
         Text("HoveredWindowUnderMovingWindow: '%s'", g.HoveredWindowUnderMovingWindow ? g.HoveredWindowUnderMovingWindow->Name : "NULL");
         Text("HoveredDockNode: 0x%08X", g.HoveredDockNode ? g.HoveredDockNode->ID : 0);
         Text("MovingWindow: '%s'", g.MovingWindow ? g.MovingWindow->Name : "NULL");
@@ -16293,7 +16386,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
                     ImRect r = Funcs::GetTableRect(table, cfg->ShowTablesRectsType, column_n);
                     ImU32 col = (table->HoveredColumnBody == column_n) ? IM_COL32(255, 255, 128, 255) : IM_COL32(255, 0, 128, 255);
                     float thickness = (table->HoveredColumnBody == column_n) ? 3.0f : 1.0f;
-                    draw_list->AddRect(r.Min, r.Max, col, 0.0f, ~0, thickness);
+                    draw_list->AddRect(r.Min, r.Max, col, 0.0f, 0, thickness);
                 }
             }
             else
@@ -16480,7 +16573,7 @@ void ImGui::DebugNodeDrawList(ImGuiWindow* window, ImGuiViewportP* viewport, con
                 {
                     ImDrawListFlags backup_flags = fg_draw_list->Flags;
                     fg_draw_list->Flags &= ~ImDrawListFlags_AntiAliasedLines; // Disable AA on triangle outlines is more readable for very large and thin triangles.
-                    fg_draw_list->AddPolyline(triangle, 3, IM_COL32(255, 255, 0, 255), true, 1.0f);
+                    fg_draw_list->AddPolyline(triangle, 3, IM_COL32(255, 255, 0, 255), ImDrawFlags_Closed, 1.0f);
                     fg_draw_list->Flags = backup_flags;
                 }
             }
@@ -16507,7 +16600,7 @@ void ImGui::DebugNodeDrawCmdShowMeshAndBoundingBox(ImDrawList* out_draw_list, co
         for (int n = 0; n < 3; n++, idx_n++)
             vtxs_rect.Add((triangle[n] = vtx_buffer[idx_buffer ? idx_buffer[idx_n] : idx_n].pos));
         if (show_mesh)
-            out_draw_list->AddPolyline(triangle, 3, IM_COL32(255, 255, 0, 255), true, 1.0f); // In yellow: mesh triangles
+            out_draw_list->AddPolyline(triangle, 3, IM_COL32(255, 255, 0, 255), ImDrawFlags_Closed, 1.0f); // In yellow: mesh triangles
     }
     // Draw bounding boxes
     if (show_aabb)
@@ -16650,10 +16743,10 @@ void ImGui::DebugNodeWindow(ImGuiWindow* window, const char* label)
     BulletText("DockId: 0x%04X, DockOrder: %d, Act: %d, Vis: %d", window->DockId, window->DockOrder, window->DockIsActive, window->DockTabIsVisible);
     if (window->DockNode || window->DockNodeAsHost)
         DebugNodeDockNode(window->DockNodeAsHost ? window->DockNodeAsHost : window->DockNode, window->DockNodeAsHost ? "DockNodeAsHost" : "DockNode");
-    if (window->RootWindow != window)       { DebugNodeWindow(window->RootWindow, "RootWindow"); }
-    if (window->RootWindowDockStop != window->RootWindow) { DebugNodeWindow(window->RootWindowDockStop, "RootWindowDockStop"); }
-    if (window->ParentWindow != NULL)       { DebugNodeWindow(window->ParentWindow, "ParentWindow"); }
-    if (window->DC.ChildWindows.Size > 0)   { DebugNodeWindowsList(&window->DC.ChildWindows, "ChildWindows"); }
+    if (window->RootWindow != window)           { DebugNodeWindow(window->RootWindow, "RootWindow"); }
+    if (window->RootWindowDockTree != window->RootWindow) { DebugNodeWindow(window->RootWindowDockTree, "RootWindowDockTree"); }
+    if (window->ParentWindow != NULL)           { DebugNodeWindow(window->ParentWindow, "ParentWindow"); }
+    if (window->DC.ChildWindows.Size > 0)       { DebugNodeWindowsList(&window->DC.ChildWindows, "ChildWindows"); }
     if (window->ColumnsStorage.Size > 0 && TreeNode("Columns", "Columns sets (%d)", window->ColumnsStorage.Size))
     {
         for (int n = 0; n < window->ColumnsStorage.Size; n++)