Overlap: Fixed first frame of an overlap highlighting underlying item if previous frame didn't hover anything. (#6512, #3909, #517)

docs/CHANGELOG.txt

@@ -63,10 +63,12 @@ Other changes:
     isn't covered as much. (Match offset for drag and drop tooltips)
   - IsItemHovered: Tweaked default value of style.HoverDelayNormal from 0.30 to 0.40,
     Tweaked default value of style.HoverDelayShort from 0.10 to 0.15. (#1485)
+- Overlapping items: (#6512, #3909, #517)
+  - Selectable, TreeNode: When using ImGuiSelectableFlags_AllowOverlap/ImGuiTreeNodeFlags_AllowOverlap
+    and holding item held, overlapping widgets won't appear as hovered. (#6512, #3909)
+  - Fixed first frame of an overlap highlighting underlying item if previous frame didn't hover anything.
 - IsWindowHovered: Added support for ImGuiHoveredFlags_Stationary.
 - IsWindowHovered, IsItemHovered: Assert when passed any unsupported flags.
-- Selectable, TreeNode: When using ImGuiSelectableFlags_AllowOverlap/ImGuiTreeNodeFlags_AllowOverlap
-  and holding item held, overlapping widgets won't appear as hovered. (#6512, #3909)
 - Tables: Fixed a regression in 1.89.6 leading to the first column of tables with either
   ScrollX or ScrollY flags from being impossible to resize. (#6503)
 - CollapsingHeader/TreeNode: Fixed text padding when using _Framed+_Leaf flags. (#6549) [@BobbyAnguelov]

imgui.h

@@ -23,7 +23,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM >= 12345')
 #define IMGUI_VERSION       "1.89.7 WIP"
-#define IMGUI_VERSION_NUM   18965
+#define IMGUI_VERSION_NUM   18966
 #define IMGUI_HAS_TABLE
 
 /*

imgui_widgets.cpp

@@ -524,7 +524,7 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
         g.HoveredWindow = backup_hovered_window;
 
     // AllowOverlap mode (rarely used) requires previous frame HoveredId to be null or to match. This allows using patterns where a later submitted widget overlaps a previous one.
-    if (hovered && (flags & ImGuiButtonFlags_AllowItemOverlap) && (g.HoveredIdPreviousFrame != id && g.HoveredIdPreviousFrame != 0))
+    if (hovered && (flags & ImGuiButtonFlags_AllowItemOverlap) && g.HoveredIdPreviousFrame != id)
         hovered = false;
 
     // Mouse handling