Ticket #29887: 29887.patch

src/wp-includes/js/mediaelement/wp-mediaelement.js

@@ -28 +28 @@
                         }
                 };
 
+                // mediaelement needs the height that wp sets on .wp-video to correctly size the player
+                // but the container height should be set to auto for responsive video embeds
+                $('.wp-video').css('height', 'auto'); 
+
                 $('.wp-audio-shortcode, .wp-video-shortcode').mediaelementplayer( settings );
         });