What is the best practice for adding "Disposition-Notification-To" in the email header for send/read receipts in PHP?

When adding the "Disposition-Notification-To" header in an email for send/read receipts in PHP, it is best practice to ensure that the recipient's email address is set correctly to receive the notifications. This header allows the recipient's email client to send a notification when the email is successfully delivered or read. To implement this in PHP, you can simply add the header using the mail() function when sending the email.

$to = "recipient@example.com";
$subject = "Your Subject Here";
$message = "Your Message Here";
$headers = "Disposition-Notification-To: your_email@example.com\r\n";

// Send email with the header
mail($to, $subject, $message, $headers);