Add a container to wrap a video oembed field and make it responsive.

format_video_profile_field.php

<?php
/**
 * Wrap the oembed video in a div so we can use custom CSS to make the video responsive inside the container.
 * You must also add the following custom CSS to your site:
 * .video-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; }
 * .video-container iframe { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
 */
function format_media_profile_field( $value, $original_value, $field_name ) {
    // Define the fields that should use the 'media-container' class
    $responsive_fields = array( 'video_link_1', 'video_link_2', 'video_link_3' );

    // Return early if the field name is not in the responsive fields array
    if ( ! in_array( $field_name, $responsive_fields, true ) ) {
        return $value;
    }

    // Wrap the value in a div with the 'media-container' class
    return '<div class="video-container">' . $value . '</div>';
}
add_filter( 'pmpromd_format_profile_field', 'format_media_profile_field', 10, 3 );