/youtu.be

missing S for httpS (was missing) on line 598

‘youtu_be’ => ‘https://youtu.be/(%5Ba-z0-9_-%5D{11})’,

added to allow the plugin to catch a video when added directly to the editor to respond correctly with the browser size.

https://ww.wp.xz.cn/plugins/advanced-responsive-video-embedder/