Thickbox is needed for the media modal back-compat. Are there plugins that still use this? Also needed for PressThis. See #24067.

git-svn-id: https://develop.svn.wordpress.org/trunk@26898 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-editor.php

@@ -487,7 +487,7 @@ final class _WP_Editors {
 			wp_enqueue_script('wp-fullscreen');
 
 		if ( self::$has_medialib ) {
-	//		add_thickbox(); // ?
+			add_thickbox();
 			wp_enqueue_script('media-upload');
 		}
 	}