diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 59f268ff0..062b1bc90 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -81,11 +81,15 @@ Other Changes:
     - TextLink() underline thickness.
     - ColorButton() border thickness.
     - Separator() thickness, via scaling newly added style.SeparatorSize. (#2657, #9263)
-- Demo: fixed IMGUI_DEMO_MARKER locations for examples applets. (#9261, #3689) [@pthom]
 - Clipper:
   - Clear `DisplayStart`/`DisplayEnd` fields when `Step()` returns false.
   - Added `UserIndex` helper storage. This is solely a convenience for cases where
     you may want to carry an index around.
+- Scrollbar:
+  - Implemented a custom tweak to extend hit-testing bounding box when window is sitting
+    at the edge of a viewport (e.g. fullscreen or docked window), so that e.g. mouse the
+    mouse at the extreme of the screen will reach the scrollbar. (#9276)
+- Demo: fixed IMGUI_DEMO_MARKER locations for examples applets. (#9261, #3689) [@pthom]
 - Backends:
   - SDLGPU3: removed unnecessary call to SDL_WaitForGPUIdle when releasing
     vertex/index buffers. (#9262) [@jaenis]
diff --git a/imgui_internal.h b/imgui_internal.h
index 0d229e6c2..ee9847393 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -3643,6 +3643,7 @@ namespace ImGui
     IMGUI_API ImGuiID       GetWindowScrollbarID(ImGuiWindow* window, ImGuiAxis axis);
     IMGUI_API ImGuiID       GetWindowResizeCornerID(ImGuiWindow* window, int n); // 0..3: corners
     IMGUI_API ImGuiID       GetWindowResizeBorderID(ImGuiWindow* window, ImGuiDir dir);
+    IMGUI_API void          ExtendHitBoxWhenNearViewportEdge(ImGuiWindow* window, ImRect* bb, float threshold, ImGuiAxis axis);
 
     // Widgets low-level behaviors
     IMGUI_API bool          ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool* out_held, ImGuiButtonFlags flags = 0);
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index f1837920c..97e297caa 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -974,6 +974,16 @@ ImRect ImGui::GetWindowScrollbarRect(ImGuiWindow* window, ImGuiAxis axis)
         return ImRect(ImMax(outer_rect.Min.x, outer_rect.Max.x - border_size - scrollbar_size), inner_rect.Min.y + border_top, outer_rect.Max.x - border_size, inner_rect.Max.y - border_size);
 }
 
+void ImGui::ExtendHitBoxWhenNearViewportEdge(ImGuiWindow* window, ImRect* bb, float threshold, ImGuiAxis axis)
+{
+    ImRect window_rect = window->RootWindow->Rect();
+    ImRect viewport_rect = window->Viewport->GetMainRect();
+    if (window_rect.Min[axis] == viewport_rect.Min[axis] && bb->Min[axis] > window_rect.Min[axis] && bb->Min[axis] - threshold <= window_rect.Min[axis])
+        bb->Min[axis] = window_rect.Min[axis];
+    if (window_rect.Max[axis] == viewport_rect.Max[axis] && bb->Max[axis] < window_rect.Max[axis] && bb->Max[axis] + threshold >= window_rect.Max[axis])
+        bb->Max[axis] = window_rect.Max[axis];
+}
+
 void ImGui::Scrollbar(ImGuiAxis axis)
 {
     ImGuiContext& g = *GImGui;
@@ -1035,11 +1045,15 @@ bool ImGui::ScrollbarEx(const ImRect& bb_frame, ImGuiID id, ImGuiAxis axis, ImS6
     const float grab_h_pixels = ImClamp(scrollbar_size_v * ((float)size_visible_v / (float)win_size_v), grab_h_minsize, scrollbar_size_v);
     const float grab_h_norm = grab_h_pixels / scrollbar_size_v;
 
+    // As a special thing, we allow scrollbar near the edge of a screen/viewport to be reachable with mouse at the extreme edge (#9276)
+    ImRect bb_hit = bb_frame;
+    ExtendHitBoxWhenNearViewportEdge(window, &bb_hit, g.Style.WindowBorderSize, (ImGuiAxis)(axis ^ 1));
+
     // Handle input right away. None of the code of Begin() is relying on scrolling position before calling Scrollbar().
     bool held = false;
     bool hovered = false;
     ItemAdd(bb_frame, id, NULL, ImGuiItemFlags_NoNav);
-    ButtonBehavior(bb, id, &hovered, &held, ImGuiButtonFlags_NoNavFocus);
+    ButtonBehavior(bb_hit, id, &hovered, &held, ImGuiButtonFlags_NoNavFocus);
 
     const ImS64 scroll_max = ImMax((ImS64)1, size_contents_v - size_visible_v);
     float scroll_ratio = ImSaturate((float)*p_scroll_v / (float)scroll_max);