Fix crash on broken list widget

Editor assessment

The subject states the fix plainly: a crash on a broken list widget is corrected, with the issue reference conventionally attached. The failure scenario is concrete and understandable without the diff. The fix type matches a defensive correction. The body consists solely of the standard cherry-pick provenance line, which is conventional rather than noise and appropriate for a backported fix. No scope is needed since the widget is named. Style is clean apart from the doubled 'fix: Fix' opener. Good and publishable.