diff --git a/wp-includes/js/media-views.js b/wp-includes/js/media-views.js
index 1050420044..a045499995 100644
--- a/wp-includes/js/media-views.js
+++ b/wp-includes/js/media-views.js
@@ -661,6 +661,10 @@
 				return !! this.mirroring.getByCid( attachment.cid ) && ! edit.getByCid( attachment.cid ) && media.model.Selection.prototype.validator.apply( this, arguments );
 			};
 
+			// Reset the library to ensure that all attachments are re-added
+			// to the collection. Do so silently, as calling `observe` will
+			// trigger the `reset` event.
+			library.reset( library.mirroring.models, { silent: true });
 			library.observe( edit );
 			this.editLibrary = edit;