Index: src/wp-admin/js/press-this.js
===================================================================
--- src/wp-admin/js/press-this.js	(revision 31661)
+++ src/wp-admin/js/press-this.js	(working copy)
@@ -751,6 +751,10 @@
 			renderDetectedMedia();
 			$( document ).on( 'tinymce-editor-init', renderSuggestedContent );
 			renderStartupNotices();
+
+			if (window.tagBox) {
+				window.tagBox.init();
+			}
 		}
 
 		/**
Index: src/wp-admin/js/tags-box.js
===================================================================
--- src/wp-admin/js/tags-box.js	(revision 31661)
+++ src/wp-admin/js/tags-box.js	(working copy)
@@ -195,8 +195,4 @@
 		}
 	};
 
-	$( document ).ready( function() {
-		tagBox.init();
-	});
-
 }( jQuery ));