diff --git a/packages/block-editor/src/components/block-list-appender/index.js b/packages/block-editor/src/components/block-list-appender/index.js
index df075295b58bd..fc1e624e9a15d 100644
--- a/packages/block-editor/src/components/block-list-appender/index.js
+++ b/packages/block-editor/src/components/block-list-appender/index.js
@@ -56,7 +56,7 @@ function useAppender( rootClientId, CustomAppender ) {
 					__unstableGetEditorMode() === 'zoom-out',
 				isParentSelected:
 					rootClientId === selectedBlockClientId ||
-					( rootClientId === '' && ! selectedBlockClientId ),
+					( ! rootClientId && ! selectedBlockClientId ),
 			};
 		},
 		[ rootClientId ]