add_filter('wp_check_filetype_and_ext', 'fix_h5p_ms_js_mime_type', 10, 4);
function fix_h5p_ms_js_mime_type($types, $file, $filename, $mimes) {
    // Check if the file is an H5P upgrades.js file
    if (strpos($filename, 'upgrades.js') !== false || substr($filename, -3) === '.js') {
        $types['ext']  = 'js';
        $types['type'] = 'application/javascript';
    }
    return $types;
}

// Ensure the header is set properly if served via ms-files.php
add_filter('ms_synced_mime_types', 'add_js_to_ms_synced_mimes');
function add_js_to_ms_synced_mimes($mimes) {
    $mimes['js'] = 'application/javascript';
    return $mimes;
}

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="https://web.colby.edu/wp-sitemap-index.xsl" ?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"><sitemap><loc>https://web.colby.edu/wp-sitemap-posts-page-1.xml</loc></sitemap></sitemapindex>