I want to pass a parameter to a page from the one visited before and use it in a shortcode function. For this, I am writing in the scope of a function in functions.php :
But it always return empty. What is the correct way to do this ?
My guess is that functions.php has an empty $_POST when called as it is called by an other file, not directly by the user. How can I access the _POST data in functions.php then ?