Tables: Fixed bottom-most and right-most outer border offset by one. (#6765, #3752)

docs/CHANGELOG.txt

@@ -56,6 +56,7 @@ Other changes:
 - Nav: Tabbing always enable nav highlight when ImGuiConfigFlags_NavEnableKeyboard is set.
   Previously was inconsistent and only enabled when stepping through a non-input item.
   (#6802, #3092, #5759, #787)
+- Tables: Fixed bottom-most and right-most outer border offset by one. (#6765, #3752) [@v-ein]
 - Fonts: 'float size_pixels' passed to AddFontXXX() functions is now rounded to lowest integer.
   This is because our layout/font system currently doesn't fully support non-integer sizes. Until
   it does, this has been a common pitfall leading to more or less subtle issues. (#3164, #3309, #6800)

imgui_tables.cpp

@@ -2640,7 +2640,7 @@ void ImGui::TableDrawBorders(ImGuiTable* table)
         const ImU32 outer_col = table->BorderColorStrong;
         if ((table->Flags & ImGuiTableFlags_BordersOuter) == ImGuiTableFlags_BordersOuter)
         {
-            inner_drawlist->AddRect(outer_border.Min, outer_border.Max, outer_col, 0.0f, 0, border_size);
+            inner_drawlist->AddRect(outer_border.Min, outer_border.Max + ImVec2(1, 1), outer_col, 0.0f, 0, border_size);
         }
         else if (table->Flags & ImGuiTableFlags_BordersOuterV)
         {