add_filter( 'the_password_form', 'wpse_71284_custom_post_password_msg' );
/**
* Add a message to the password form.
*
* @wp-hook the_password_form
* @param string $form
* @return string
*/
function wpse_71284_custom_post_password_msg( $form )
{
// No cookie, the user has not sent anything until now.
if ( ! isset ( $_COOKIE[ 'wp-postpass_' . COOKIEHASH ] ) ) {
return $form;
}
if (wp_get_referer()== get_permalink()) {
// Translate and escape.
$msg= esc_html__( 'Sorry, your password is wrong.', 'your_text_domain' );
// We have a cookie, but it doesn’t match the password.
$msg= "<p class='custom-password-message'>$msg</p>";
return $msg . $form;
}
return $form;
}
