<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0-alpha1/dist/css/bootstrap.min.css" rel="stylesheet"
        integrity="sha384-GLhlTQ8iRABdZLl6O3oVMWSktQOp6b7In1Zl3/Jr59b6EGGoI1aFkw7cmDA6j6gD" crossorigin="anonymous">
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.3.0/css/all.min.css"
        integrity="sha512-SzlrxWUlpfuzQ+pcUCosxcglQRNAq/DZjVsC0lE40xsADsfeQoEypE+enwcOiGjk/bSuGGKHEyjSoQ1zVisanQ=="
        crossorigin="anonymous" referrerpolicy="no-referrer" />
</head>
</html>
<?php

add_action( 'wpcf7_init', 'wpcf7_add_form_tag_hidden', 10, 0 );

function wpcf7_add_form_tag_hidden() {
	wpcf7_add_form_tag( 'hidden',
		'wpcf7_hidden_form_tag_handler',
		array(
			'name-attr' => true,
			'display-hidden' => true,
		)
	);
}

function wpcf7_hidden_form_tag_handler( $tag ) {
	if ( empty( $tag->name ) ) {
		return '';
	}

	$atts = array();

	$class = wpcf7_form_controls_class( $tag->type );
	$atts['class'] = $tag->get_class_option( $class );
	$atts['id'] = $tag->get_id_option();

	$value = (string) reset( $tag->values );
	$value = $tag->get_default_option( $value );
	$atts['value'] = $value;

	$atts['type'] = 'hidden';
	$atts['name'] = $tag->name;
	$atts = wpcf7_format_atts( $atts );

	$html = sprintf( '<input %s />', $atts );
	return $html;
}
