Adding Custom attributes to Oembed WordPress

functions.php

<?php
/**
 * Add 'id' attribute to Vimeo oEmbed HTML
 */
function prefix_embed_oembed_html( $html, $url, $attr, $post_ID ) {
	$fix  = true;
	$fix &= strpos( $html, 'youtube.com' ) !== false; // Embed code from Vimeo
	$fix &= strpos( $html, ' id=' ) === false; // No ID attribute supplied by Vimeo
	$fix &= isset( $attr['player_id'] ); // Player ID supplied

	if ( $fix ) {
		$html = str_replace(
			'<iframe ',
			sprintf( '<iframe id="%s" ', esc_attr( $attr['player_id'] ) ),
			$html
		);
	}
	
	return $html;
}

add_filter( 'embed_oembed_html', 'prefix_embed_oembed_html', 10, 4 );