Multi-Select + Tables: fixed an issue which could lead to an extra vertical offset in the Header row. (#8250, #7994) Because BeginMultiSelect() does `ms->ScopeRectMin = window->DC.CursorMaxPos = window->DC.CursorPos` at a time where CursorPos is already past MaxPos.y because of ItemSpacing.y. Accumulate spacing.

diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 42e4f79..9a3e84f 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt

@@ -61,6 +61,8 @@
 - Multi-Select:
   - Fixed an issue using Multi-Select within a Table causing column width measurement to
     be invalid when trailing column contents is not submitted in the last row. (#9341, #8250)
+  - Fixed an issue using Multi-Select within a Table with the right-most column visible,
+    which could lead to an extra vertical offset in the Header row. (#8250)
   - Box-Select: fixed an issue using ImGuiMultiSelectFlags_BoxSelect1d mode while scrolling.
     Notably, using mouse wheel while holding a box-selection could lead items close to windows
     edges from not being correctly unselected. (#7994, #8250, #7821, #7850, #7970)

diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index d4f7c0e..3d9f2be 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp

@@ -8016,7 +8016,9 @@
     ms->FocusScopeId = id;
     ms->Flags = flags;
     ms->BackupCursorMaxPos = window->DC.CursorMaxPos;
-    ms->ScopeRectMin = window->DC.CursorMaxPos = window->DC.CursorPos; // CalcScopeRect() for ImGuiMultiSelectFlags_ScopeRect will measure in EndMultiSelect().
+    ms->ScopeRectMin = window->DC.CursorPos;
+    if (flags & ImGuiMultiSelectFlags_ScopeRect)
+        window->DC.CursorMaxPos = ms->ScopeRectMin; // CalcScopeRect() for ImGuiMultiSelectFlags_ScopeRect will measure in EndMultiSelect().
     PushFocusScope(ms->FocusScopeId);
     ms->IsFocused = IsInNavFocusRoute(g.CurrentFocusScopeId);
     if (flags & ImGuiMultiSelectFlags_ScopeWindow) // Mark parent child window as navigable into, with highlight. Assume user will always submit interactive items.