Ticket #54960: 54960.patch

src/js/media/views/attachments/browser.js

@@ -130 +130 @@
                         mediaFoundHasMoreResultsMessage = __( 'Number of media items displayed: %d. Scroll the page for more results.' );
                 }
 
-                if ( this.collection.mirroring.args.s ) {
+                if (this.collection.hasOwnProperty('mirroring') && this.collection.mirroring.args.s) {
                         count = this.collection.length;
 
                         if ( 0 === count ) {