<!DOCTYPE html>
<html>
  <head>
    <title>{{ .Site.Title }}</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="{{ relURL "/css/main.css" }}">
  </head>
  <body>
    <h1 id="site-title"><a href="{{ relURL "/" }}">{{ .Site.Title }}</a></h1>

<!DOCTYPE html>
<html>
  <head>
    <title>{{ .Site.Title }}</title>
    {{ .Hugo.Generator }}
    {{ "<!-- Tumble theme for Hugo: https://github.com/adrianshort/tumble -->" | safeHTML }}
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="{{ relURL "/css/main.css" }}">
  </head>
  <body>
    <h1 id="site-title"><a href="{{ relURL "/" }}">{{ .Site.Title }}</a></h1>

Add generator tag and comment link to theme code
Add generator tag and comment link to theme code

How to preserve HTML comments in Go templates:

https://discourse.gohugo.io/t/how-to-add-comments-in-a-template/75/8
