message: Combo: Offset popup position by border size so that a double border isn't so visible.
diff: @@ -8882,12 +8882,12 @@ bool ImGui::BeginCombo(const char* label, const char* preview_value, ImVec2 popu
  // Position our combo ABOVE because there's more space to fit! (FIXME: Handle in Begin() or use a shared helper. We have similar code in Begin() for popup placement)
  popup_y1 = ImClamp(frame_bb.Min.y - popup_size.y, style.DisplaySafeAreaPadding.y, frame_bb.Min.y);
  popup_y2 = frame_bb.Min.y;
  - SetNextWindowPos(ImVec2(frame_bb.Min.x, frame_bb.Min.y), ImGuiCond_Always, ImVec2(0.0f, 1.0f));
  + SetNextWindowPos(ImVec2(frame_bb.Min.x, frame_bb.Min.y + window->WindowBorderSize), ImGuiCond_Always, ImVec2(0.0f, 1.0f));
  }
  else
  {
  // Position our combo below
  - SetNextWindowPos(ImVec2(frame_bb.Min.x, frame_bb.Max.y), ImGuiCond_Always, ImVec2(0.0f, 0.0f));
  + SetNextWindowPos(ImVec2(frame_bb.Min.x, frame_bb.Max.y - window->WindowBorderSize), ImGuiCond_Always, ImVec2(0.0f, 0.0f));
  }
  SetNextWindowSize(ImVec2(popup_size.x, popup_y2 - popup_y1), ImGuiCond_Appearing);
  PushStyleVar(ImGuiStyleVar_WindowPadding, style.FramePadding);
  