Debugging WP Mail

// define the wp_mail_failed callback 
function action_wp_mail_failed($wp_error) 
{
    return error_log(print_r($wp_error, true));
}
          
// add the action 
add_action('wp_mail_failed', 'action_wp_mail_failed', 10, 1);

I personally use slack’s webhooks and other methods for this notification.

Reference:

Debugging Wp Mail like a boss debugger – CodeForest

Debugging WP Mail is hard as it only returns true or false. I am showing you a way to get those WP Mail

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