diff --git a/wp-includes/media.php b/wp-includes/media.php
index a7239297ab..76cc0c11c9 100644
--- a/wp-includes/media.php
+++ b/wp-includes/media.php
@@ -2556,7 +2556,11 @@ function wp_video_shortcode( $attr, $content = '' ) {
 		} elseif ( $is_vimeo ) {
 			// Remove all query arguments and force SSL - see #40866.
 			$parsed_vimeo_url = wp_parse_url( $atts['src'] );
-			$atts['src'] = 'https://' . $parsed_vimeo_url['host'] . $parsed_vimeo_url['path'];
+			$vimeo_src = 'https://' . $parsed_vimeo_url['host'] . $parsed_vimeo_url['path'];
+
+			// Add loop param for mejs bug - see #40977, not needed after #39686.
+			$loop = $atts['loop'] ? '1' : '0';
+			$atts['src'] = add_query_arg( 'loop', $loop, $vimeo_src );
 		}
 	}
 
diff --git a/wp-includes/widgets/class-wp-widget-media-video.php b/wp-includes/widgets/class-wp-widget-media-video.php
index dd90bfac6b..f05928f636 100644
--- a/wp-includes/widgets/class-wp-widget-media-video.php
+++ b/wp-includes/widgets/class-wp-widget-media-video.php
@@ -115,13 +115,9 @@ class WP_Widget_Media_Video extends WP_Widget_Media {
 			$attachment = get_post( $instance['attachment_id'] );
 		}
 
+		$src = $instance['url'];
 		if ( $attachment ) {
 			$src = wp_get_attachment_url( $attachment->ID );
-		} else {
-
-			// Manually add the loop query argument.
-			$loop = $instance['loop'] ? '1' : '0';
-			$src = empty( $instance['url'] ) ? $instance['url'] : add_query_arg( 'loop', $loop, $instance['url'] );
 		}
 
 		if ( empty( $src ) ) {