Index: src/wp-includes/media.php
===================================================================
--- src/wp-includes/media.php	(revision 54119)
+++ src/wp-includes/media.php	(working copy)
@@ -3219,6 +3219,7 @@
  *     @type string $poster   The 'poster' attribute for the `<video>` element. Default empty.
  *     @type string $loop     The 'loop' attribute for the `<video>` element. Default empty.
  *     @type string $autoplay The 'autoplay' attribute for the `<video>` element. Default empty.
+ *     @type string $muted    The 'muted' attribute for the `<video>` element. Default false.
  *     @type string $preload  The 'preload' attribute for the `<video>` element.
  *                            Default 'metadata'.
  *     @type string $class    The 'class' attribute for the `<video>` element.
@@ -3263,6 +3264,7 @@
 		'poster'   => '',
 		'loop'     => '',
 		'autoplay' => '',
+		'muted'    => 'false',
 		'preload'  => 'metadata',
 		'width'    => 640,
 		'height'   => 360,
@@ -3390,11 +3392,12 @@
 		'poster'   => esc_url( $atts['poster'] ),
 		'loop'     => wp_validate_boolean( $atts['loop'] ),
 		'autoplay' => wp_validate_boolean( $atts['autoplay'] ),
+		'muted'    => wp_validate_boolean( $atts['muted'] ),
 		'preload'  => $atts['preload'],
 	);
 
 	// These ones should just be omitted altogether if they are blank.
-	foreach ( array( 'poster', 'loop', 'autoplay', 'preload' ) as $a ) {
+	foreach ( array( 'poster', 'loop', 'autoplay', 'preload', 'muted' ) as $a ) {
 		if ( empty( $html_atts[ $a ] ) ) {
 			unset( $html_atts[ $a ] );
 		}
Index: tests/phpunit/tests/media.php
===================================================================
--- tests/phpunit/tests/media.php	(revision 54119)
+++ tests/phpunit/tests/media.php	(working copy)
@@ -1023,6 +1023,7 @@
 
 	/**
 	 * @ticket 35367
+	 * @ticket 54788
 	 * @depends test_video_shortcode_body
 	 */
 	public function test_wp_video_shortcode_attributes() {
@@ -1035,6 +1036,7 @@
 		$this->assertStringContainsString( 'src="https://example.com/foo.mp4', $actual );
 		$this->assertStringNotContainsString( 'loop', $actual );
 		$this->assertStringNotContainsString( 'autoplay', $actual );
+		$this->assertStringNotContainsString( 'muted', $actual );
 		$this->assertStringContainsString( 'preload="metadata"', $actual );
 		$this->assertStringContainsString( 'width="640"', $actual );
 		$this->assertStringContainsString( 'height="360"', $actual );
@@ -1046,6 +1048,7 @@
 				'poster'   => 'https://example.com/foo.png',
 				'loop'     => true,
 				'autoplay' => true,
+				'muted'    => true,
 				'preload'  => true,
 				'width'    => 123,
 				'height'   => 456,
@@ -1057,6 +1060,7 @@
 		$this->assertStringContainsString( 'poster="https://example.com/foo.png', $actual );
 		$this->assertStringContainsString( 'loop="1"', $actual );
 		$this->assertStringContainsString( 'autoplay="1"', $actual );
+		$this->assertStringContainsString( 'muted', $actual );
 		$this->assertStringContainsString( 'preload="1"', $actual );
 		$this->assertStringContainsString( 'width="123"', $actual );
 		$this->assertStringContainsString( 'height="456"', $actual );