/usr/share/cherokee/themes/plain/header.html is in libcherokee-server0 1.2.101-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22  | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
 <meta http-equiv="content-type" content="text/html; charset=utf-8" />
 <link rel="stylesheet" type="text/css" media="screen" href="/cherokee_themes/plain/theme.css" />
 <title>Index of %public_dir%</title>
</head>
<body>
 <pre class="header">%notice%</pre>
 <h2>Index of %public_dir%</h2>
 <div class="list">
 <table summary="Directory Listing" cellpadding="0" cellspacing="0">
  <thead>
   <tr>
    <th><a href="?order=%order_name%">Name</a></th>
    %if size%<th class="s"><a href="?order=%order_size%">Size</a></th>%fi%
    %if date%<th class="m"><a href="?order=%order_date%">Last Modified</a></th>%fi%
    %if user%<th class="u"><a href="#">User</a></th>%fi%
    %if group%<th class="g"><a href="#">Group</a></th>%fi%
   </tr>
  </thead>
  <tbody>
 |