diff --git a/packages/format-library/src/link/use-link-instance-key.js b/packages/format-library/src/link/use-link-instance-key.js
index 7f16a83554446b..5d491a091436e2 100644
--- a/packages/format-library/src/link/use-link-instance-key.js
+++ b/packages/format-library/src/link/use-link-instance-key.js
@@ -17,6 +17,9 @@ function getKey( _id ) {
  * @return {string} the unique key to use for this link control.
  */
 function useLinkInstanceKey( instance ) {
+	if ( ! instance ) {
+		return;
+	}
 	if ( weakMap.has( instance ) ) {
 		return getKey( weakMap.get( instance ) );
 	}