wp_get_default_extension_for_mime_type

WordPress Version: 8.1

/**
 * Returns first matched extension for the mime-type,
 * as mapped from wp_get_mime_types().
 *
 * @since 5.8.1
 *
 * @param string $mime_type
 *
 * @return string|false
 */
function wp_get_default_extension_for_mime_type($mime_type)
{
    $extensions = explode('|', array_search($mime_type, wp_get_mime_types(), true));
    if (empty($extensions[0])) {
        return false;
    }
    return $extensions[0];
}