Override html.tpl.php per node type does not work I saw that this was asked few times before, and I tried the answers, and I tried modifying the answers, yet nothing.

Case:
I have Advanced Forum installed, and I am using HTML5 Application Cache (appcache) (don't you dear to run away now!).

Obviously I need to turn appcache off when surffing forums, and I managed to make custom html.tpl.html for /forum and /forums, so when I am looking forum list and topic list I won't get cached.

But then:
When I am looking at forum topic, it is a post ofc, and post type (machine type is forum) and I have defined in template.php:

$node = menu_get_object();

if ($node &amp;&amp; $node-&gt;nid) {
    $vars['theme_hook_suggestion'][] = 'html__' . $node-&gt;type;
}


and it won't make change. 

So I am able to change html.tpl.php for path but not for node type.

Help me please and correct my knowledge for making such things.

Thanks for all!!!
(btw i dont need a lesson of appcache, sincerely if you have manifest = x.appcache" in your html tag it will cache it, even if it's in network section)
you don't need different template for this. 
you can set variable in preprocess function and print it.

function MYTHEME_preprocess_html (&amp;$variables, $hook) 
  $node = menu_get_object();
  $dont_cache = array('some_type');
  if (!empty($node-&gt;nid) &amp;&amp; in_array($node-&gt;type, $dont_cache)) {//check if it is node and if it shouldnt be cached
    $variables['appcache'] = '';
  }
  else {
    $variables['appcache'] = 'manifest = x.appcache';//put your value here
  } 
 }


and then print $appcache in you html.tpl.php