WordPress Version: 6.1
/**
* Outputs nonce, action, and option_page fields for a settings page.
*
* @since 2.7.0
*
* @param string $option_group A settings group name. This should match the group name
* used in register_setting().
*/
function settings_fields($option_group)
{
echo "<input type='hidden' name='option_page' value='" . esc_attr($option_group) . "' />";
echo '<input type="hidden" name="action" value="update" />';
wp_nonce_field("{$option_group}-options");
}