Internals: Added GetWindowResizeID(), renamed GetScrollbarID() to GetWindowScrollbarID(). Using integer for resize ID so they matches regardless of the pointer size.
Internals: Renamed IMGUI_USER_ERROR to IM_ASSERT_USER_ERROR().
diff --git a/imgui.cpp b/imgui.cpp
index bfe4b17..76c11c1 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -4840,10 +4840,10 @@
 
 static const ImGuiResizeGripDef resize_grip_def[4] =
 {
-    { ImVec2(1,1), ImVec2(-1,-1), 0, 3 }, // Lower right
-    { ImVec2(0,1), ImVec2(+1,-1), 3, 6 }, // Lower left
-    { ImVec2(0,0), ImVec2(+1,+1), 6, 9 }, // Upper left
-    { ImVec2(1,0), ImVec2(-1,+1), 9,12 }, // Upper right
+    { ImVec2(1,1), ImVec2(-1,-1), 0, 3 }, // Lower-right
+    { ImVec2(0,1), ImVec2(+1,-1), 3, 6 }, // Lower-left
+    { ImVec2(0,0), ImVec2(+1,+1), 6, 9 }, // Upper-left (Unused)
+    { ImVec2(1,0), ImVec2(-1,+1), 9,12 }, // Upper-right (Unused)
 };
 
 static ImRect GetResizeBorderRect(ImGuiWindow* window, int border_n, float perp_padding, float thickness)
@@ -4858,6 +4858,17 @@
     return ImRect();
 }
 
+// 0..3: corners (Lower-right, Lower-left, Unused, Unused)
+// 4..7: borders (Top, Right, Bottom, Left)
+ImGuiID ImGui::GetWindowResizeID(ImGuiWindow* window, int n)
+{
+    IM_ASSERT(n >= 0 && n <= 7);
+    ImGuiID id = window->ID;
+    id = ImHashStr("#RESIZE", 0, id);
+    id = ImHashData(&n, sizeof(int), id);
+    return id;
+}
+
 // Handle resize for: Resize Grips, Borders, Gamepad
 // Return true when using auto-fit (double click on resize grip)
 static bool ImGui::UpdateManualResize(ImGuiWindow* window, const ImVec2& size_auto_fit, int* border_held, int resize_grip_count, ImU32 resize_grip_col[4])
@@ -4895,7 +4906,7 @@
         if (resize_rect.Min.x > resize_rect.Max.x) ImSwap(resize_rect.Min.x, resize_rect.Max.x);
         if (resize_rect.Min.y > resize_rect.Max.y) ImSwap(resize_rect.Min.y, resize_rect.Max.y);
         bool hovered, held;
-        ButtonBehavior(resize_rect, window->GetID((void*)(intptr_t)resize_grip_n), &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_NoNavFocus);
+        ButtonBehavior(resize_rect, window->GetID(resize_grip_n), &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_NoNavFocus);
         //GetForegroundDrawList(window)->AddRect(resize_rect.Min, resize_rect.Max, IM_COL32(255, 255, 0, 255));
         if (hovered || held)
             g.MouseCursor = (resize_grip_n & 1) ? ImGuiMouseCursor_ResizeNESW : ImGuiMouseCursor_ResizeNWSE;
@@ -4921,7 +4932,7 @@
     {
         bool hovered, held;
         ImRect border_rect = GetResizeBorderRect(window, border_n, grip_hover_inner_size, WINDOWS_RESIZE_FROM_EDGES_HALF_THICKNESS);
-        ButtonBehavior(border_rect, window->GetID((void*)(intptr_t)(border_n + 4)), &hovered, &held, ImGuiButtonFlags_FlattenChildren);
+        ButtonBehavior(border_rect, window->GetID(border_n + 4), &hovered, &held, ImGuiButtonFlags_FlattenChildren);
         //GetForegroundDrawLists(window)->AddRect(border_rect.Min, border_rect.Max, IM_COL32(255, 255, 0, 255));
         if ((hovered && g.HoveredIdTimer > WINDOWS_RESIZE_FROM_EDGES_FEEDBACK_TIMER) || held)
         {
@@ -5822,14 +5833,14 @@
     // Error checking: verify that user hasn't called End() too many times!
     if (g.CurrentWindowStack.Size <= 1 && g.WithinFrameScopeWithImplicitWindow)
     {
-        IMGUI_USER_ERROR(g.CurrentWindowStack.Size > 1, "Calling End() too many times!");
+        IM_ASSERT_USER_ERROR(g.CurrentWindowStack.Size > 1, "Calling End() too many times!");
         return;
     }
     IM_ASSERT(g.CurrentWindowStack.Size > 0);
 
     // Error checking: verify that user doesn't directly call End() on a child window.
     if (window->Flags & ImGuiWindowFlags_ChildWindow)
-        IMGUI_USER_ERROR(g.WithinEndChild, "Must call EndChild() and not End()!");
+        IM_ASSERT_USER_ERROR(g.WithinEndChild, "Must call EndChild() and not End()!");
 
     // Close anything that is open
     if (window->DC.CurrentColumns)
@@ -7003,13 +7014,13 @@
     {
         if (g.CurrentWindowStack.Size > 1)
         {
-            IMGUI_USER_ERROR(g.CurrentWindowStack.Size == 1, "Mismatched Begin/BeginChild vs End/EndChild calls: did you forget to call End/EndChild?");
+            IM_ASSERT_USER_ERROR(g.CurrentWindowStack.Size == 1, "Mismatched Begin/BeginChild vs End/EndChild calls: did you forget to call End/EndChild?");
             while (g.CurrentWindowStack.Size > 1)
                 End();
         }
         else
         {
-            IMGUI_USER_ERROR(g.CurrentWindowStack.Size == 1, "Mismatched Begin/BeginChild vs End/EndChild calls: did you call End/EndChild too much?");
+            IM_ASSERT_USER_ERROR(g.CurrentWindowStack.Size == 1, "Mismatched Begin/BeginChild vs End/EndChild calls: did you call End/EndChild too much?");
         }
     }
 
diff --git a/imgui_internal.h b/imgui_internal.h
index 027d380..e6329b2 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -166,8 +166,8 @@
 #define IM_ROUND(_VAL)                  ((float)(int)((_VAL) + 0.5f))                           //
 
 // Error handling
-#ifndef IMGUI_USER_ERROR
-#define IMGUI_USER_ERROR(_EXPR, _MSG)   IM_ASSERT((_EXPR) && (_MSG))    // Recoverable User Error
+#ifndef IM_ASSERT_USER_ERROR
+#define IM_ASSERT_USER_ERROR(_EXPR,_MSG) IM_ASSERT((_EXPR) && (_MSG))    // Recoverable User Error
 #endif
 
 // Debug Logging
@@ -1712,7 +1712,8 @@
     IMGUI_API bool          ArrowButtonEx(const char* str_id, ImGuiDir dir, ImVec2 size_arg, ImGuiButtonFlags flags);
     IMGUI_API void          Scrollbar(ImGuiAxis axis);
     IMGUI_API bool          ScrollbarEx(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* p_scroll_v, float avail_v, float contents_v, ImDrawCornerFlags rounding_corners);
-    IMGUI_API ImGuiID       GetScrollbarID(ImGuiWindow* window, ImGuiAxis axis);
+    IMGUI_API ImGuiID       GetWindowScrollbarID(ImGuiWindow* window, ImGuiAxis axis);
+    IMGUI_API ImGuiID       GetWindowResizeID(ImGuiWindow* window, int n); // 0..3: corners, 4..7: borders
     IMGUI_API void          SeparatorEx(ImGuiSeparatorFlags flags);
 
     // Widgets low-level behaviors
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index beeffba..0277c03 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -774,7 +774,7 @@
     return pressed;
 }
 
-ImGuiID ImGui::GetScrollbarID(ImGuiWindow* window, ImGuiAxis axis)
+ImGuiID ImGui::GetWindowScrollbarID(ImGuiWindow* window, ImGuiAxis axis)
 {
     return window->GetIDNoKeepAlive(axis == ImGuiAxis_X ? "#SCROLLX" : "#SCROLLY");
 }
@@ -881,7 +881,7 @@
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
 
-    const ImGuiID id = GetScrollbarID(window, axis);
+    const ImGuiID id = GetWindowScrollbarID(window, axis);
     KeepAliveID(id);
 
     // Calculate scrollbar bounding box
@@ -3464,8 +3464,8 @@
 
     const bool user_clicked = hovered && io.MouseClicked[0];
     const bool user_nav_input_start = (g.ActiveId != id) && ((g.NavInputId == id) || (g.NavActivateId == id && g.NavInputSource == ImGuiInputSource_NavKeyboard));
-    const bool user_scroll_finish = is_multiline && state != NULL && g.ActiveId == 0 && g.ActiveIdPreviousFrame == GetScrollbarID(draw_window, ImGuiAxis_Y);
-    const bool user_scroll_active = is_multiline && state != NULL && g.ActiveId == GetScrollbarID(draw_window, ImGuiAxis_Y);
+    const bool user_scroll_finish = is_multiline && state != NULL && g.ActiveId == 0 && g.ActiveIdPreviousFrame == GetWindowScrollbarID(draw_window, ImGuiAxis_Y);
+    const bool user_scroll_active = is_multiline && state != NULL && g.ActiveId == GetWindowScrollbarID(draw_window, ImGuiAxis_Y);
 
     bool clear_active_id = false;
     bool select_all = (g.ActiveId != id) && ((flags & ImGuiInputTextFlags_AutoSelectAll) != 0 || user_nav_input_start) && (!is_multiline);
@@ -6472,7 +6472,7 @@
     ImGuiTabBar* tab_bar = g.CurrentTabBar;
     if (tab_bar == NULL)
     {
-        IMGUI_USER_ERROR(tab_bar != NULL, "Mismatched BeginTabBar()/EndTabBar()!");
+        IM_ASSERT_USER_ERROR(tab_bar != NULL, "Mismatched BeginTabBar()/EndTabBar()!");
         return;
     }
     if (tab_bar->WantLayout)
@@ -6869,7 +6869,7 @@
     ImGuiTabBar* tab_bar = g.CurrentTabBar;
     if (tab_bar == NULL)
     {
-        IMGUI_USER_ERROR(tab_bar, "BeginTabItem() Needs to be called between BeginTabBar() and EndTabBar()!");
+        IM_ASSERT_USER_ERROR(tab_bar, "BeginTabItem() Needs to be called between BeginTabBar() and EndTabBar()!");
         return false;
     }
     bool ret = TabItemEx(tab_bar, label, p_open, flags);