myapp/app/views/layouts/application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>MyApp</title>
<meta name="viewport" content="width=device-width,initial-scale=1">
<%= csrf_meta_tags %>
<%= csp_meta_tag %>
<%= stylesheet_link_tag "application", "data-turbo-track": "reload", defer: true %>
<%= javascript_importmap_tags %>
</head>
<body>
<%= render "header" %>
<%= yield %>
</body>
</html>