diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 3726422c8..30261158e 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -43,6 +43,8 @@ Breaking changes:
 
 - Reordered various ImGuiInputTextFlags values. This should not be breaking unless
   you are using generated headers that have values not matching the main library.
+- Removed ImGuiButtonFlags_MouseButtonDefault_ = ImGuiButtonFlags_MouseButtonLeft
+  from imgui.h, was mostly unused and misleading.
 
 Other changes:
 
diff --git a/imgui.cpp b/imgui.cpp
index 8295cb0cf..60a686a1e 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -431,6 +431,7 @@ CODE
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
  - 2024/06/06 (1.90.8) - reordered ImGuiInputTextFlags values. This should not be breaking unless you are using generated headers that have values not matching the main library.
+ - 2024/06/06 (1.90.8) - removed 'ImGuiButtonFlags_MouseButtonDefault_ = ImGuiButtonFlags_MouseButtonLeft', was mostly unused and misleading.
  - 2024/05/27 (1.90.7) - commented out obsolete symbols marked obsolete in 1.88 (May 2022):
                             - old: CaptureKeyboardFromApp(bool)
                             - new: SetNextFrameWantCaptureKeyboard(bool)
diff --git a/imgui.h b/imgui.h
index 7acc9e69e..a5d0845bd 100644
--- a/imgui.h
+++ b/imgui.h
@@ -1657,10 +1657,8 @@ enum ImGuiButtonFlags_
     ImGuiButtonFlags_MouseButtonLeft        = 1 << 0,   // React on left mouse button (default)
     ImGuiButtonFlags_MouseButtonRight       = 1 << 1,   // React on right mouse button
     ImGuiButtonFlags_MouseButtonMiddle      = 1 << 2,   // React on center mouse button
-
-    // [Internal]
-    ImGuiButtonFlags_MouseButtonMask_       = ImGuiButtonFlags_MouseButtonLeft | ImGuiButtonFlags_MouseButtonRight | ImGuiButtonFlags_MouseButtonMiddle,
-    ImGuiButtonFlags_MouseButtonDefault_    = ImGuiButtonFlags_MouseButtonLeft,
+    ImGuiButtonFlags_MouseButtonMask_       = ImGuiButtonFlags_MouseButtonLeft | ImGuiButtonFlags_MouseButtonRight | ImGuiButtonFlags_MouseButtonMiddle, // [Internal]
+    //ImGuiButtonFlags_MouseButtonDefault_  = ImGuiButtonFlags_MouseButtonLeft,
 };
 
 // Flags for ColorEdit3() / ColorEdit4() / ColorPicker3() / ColorPicker4() / ColorButton()
@@ -3265,7 +3263,7 @@ namespace ImGui
     static inline void  PopAllowKeyboardFocus()                                             { PopTabStop(); }
     // OBSOLETED in 1.89 (from August 2022)
     IMGUI_API bool      ImageButton(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0 = ImVec2(0, 0), const ImVec2& uv1 = ImVec2(1, 1), int frame_padding = -1, const ImVec4& bg_col = ImVec4(0, 0, 0, 0), const ImVec4& tint_col = ImVec4(1, 1, 1, 1)); // Use new ImageButton() signature (explicit item id, regular FramePadding)
-    // OBSOLETED in 1.87 (from February 2022)
+    // OBSOLETED in 1.87 (from February 2022 but more formally obsoleted April 2024)
     IMGUI_API ImGuiKey  GetKeyIndex(ImGuiKey key);                                          // Map ImGuiKey_* values into legacy native key index. == io.KeyMap[key]. When using a 1.87+ backend using io.AddKeyEvent(), calling GetKeyIndex() with ANY ImGuiKey_XXXX values will return the same value!
     //static inline ImGuiKey GetKeyIndex(ImGuiKey key)                                      { IM_ASSERT(key >= ImGuiKey_NamedKey_BEGIN && key < ImGuiKey_NamedKey_END); return key; }
 
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index 725172349..c286b2d7a 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -488,7 +488,7 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
 
     // Default only reacts to left mouse button
     if ((flags & ImGuiButtonFlags_MouseButtonMask_) == 0)
-        flags |= ImGuiButtonFlags_MouseButtonDefault_;
+        flags |= ImGuiButtonFlags_MouseButtonLeft;
 
     // Default behavior requires click + release inside bounding box
     if ((flags & ImGuiButtonFlags_PressedOnMask_) == 0)