Ok, I understand. I add this line in header.php and works:
<link rel=”stylesheet” href=”https://use.fontawesome.com/releases/v5.0.13/css/all.css” integrity=”sha384-DNOHZ68U8hZfKXOrtjWvjxusGo9WQnrNx2sqG0tfsghAvtVlRW3tvkXWZh58N9jp” crossorigin=”anonymous”>
Do I need to also copy the new header.php into child theme to save it for future updates?
Tips for custom blocks works grt, thx for support!!