MultiSelect: fixed ImGuiSelectionBasicStorage::GetNextSelectedItem() reading past the end of storage when trailing items are unselected (#9604)

docs/CHANGELOG.txt

@@ -90,6 +90,9 @@ Other Changes:
     - Fixed selectable highlight straying off the X2/Y2 clipping limit.
     - Fixed parent window work rectangle affecting the Y2 clipping limit.
     - Fixed the Y2 clipping limit overlapping bottom outer border.
+- Multi-Select:
+  - Fixed `ImGuiSelectionBasicStorage::GetNextSelectedItem()` reading one past the
+    end of storage when trailing items are unselected (#9604) [@MilosLord]
 - ImVec2: added a check for cases where a custom `IM_VEC2_CLASS_EXTRA` macro
   adds an extra `operator=` to ImVec2. This isn't supported but should not
   be needed as you should have a constructor to convert from your type to ImVec2.

imgui_widgets.cpp

@@ -8803,7 +8803,7 @@ bool ImGuiSelectionBasicStorage::GetNextSelectedItem(void** opaque_it, ImGuiID*
         it = _Storage.Data.Data;
     IM_ASSERT(it >= _Storage.Data.Data && it <= it_end);
     if (it != it_end)
-        while (it->val_i == 0 && it < it_end)
+        while (it < it_end && it->val_i == 0)
             it++;
     const bool has_more = (it != it_end);
     *opaque_it = has_more ? (void**)(it + 1) : (void**)(it);