Need help with deferring javascript

Hi
thank you for your help. I've used the following code in a custo module

function MYMODULE_js_alter(&$javascript){
  if(isset($javascript['misc/drupal.js'])) $javascript['misc/drupal.js']['weight'] = -18;
  if(isset($javascript['misc/jquery.js'])) $javascript['misc/jquery.js']['weight'] = -18;
  if(isset($javascript['misc/jquery.once.js'])) $javascript['misc/jquery.once.js']['weight'] = -18;
  if(isset($javascript['misc/ajax.js'])) $javascript['misc/ajax.js']['weight'] = -18;
  //dpm($javascript);
}

unfortunately it doesn't work as ajax.js is still put in a different aggregate than the other 3.

I can't use the defer option as it break the website.
What can I try to find out why it doesn't work?
Thank you.

ok thanks,
I guess the problem is that I cannot select which files to defer, when I select defer all javascript is deferred and some things break on the website. e.g.facets don't collapse, forms text wysiwyg editor doesn't render and so on

Hot completely, deferring javascript brakes google ads on some browsers, I have to look better into this, but if you like close it, I will update in case I need. Thank you again.

Thank you very much for your help. I'm using async code as in this page https://support.google.com/adsense/answer/3221666?hl=en
anyway the ads still don't display on random pages in all browsers when I use:

JS

Check "Enable preprocess on all JS"
Check "Resource hint src attributes found in the HTML content"
Enable every checkbox under "Optimize JavaScript Ordering"
Under "Move JS to the footer" Select "All but what is in the $all_in_footer_list"
Under "Deferred JavaScript Execution: Add The defer Tag To All Script Tags" Select "All but external scripts"
Check "Put a wrapper around inline JS if it was added in the content section incorrectly"

Every time I flush browser cache the first page I load always display ads, most pages loaded after the first one randomly don't display ads, I will update when I figure out the reason.

It seems that what was breaking my google adsense was the wrapper function that was put around the adsense inline code (adsbygoogle=window.adsbygoogle||[]).push({});
I've added $inline_js_defer_skip_list[] = 'adsbygoogle'; and $inline_js_wrap_skip_list[] = 'adsbygoogle'; in advag_mod.module and now I have the ads displaying correctly.

I've also noticed the following code in

if (module_exists('googleanalytics')) {
      $inline_js_defer_skip_list[] = '_gaq.push(["_';
      $inline_js_defer_skip_list[] = '"GoogleAnalyticsObject"';
    }

which suggests that google analytics code should not be wrpped as well. I have the analytics module installed but I noticed that the analytics inline code window.google_analytics_domain_name = ".domainname.com";window.google_analytics_uacct = "UA-XXXXXXXXX"; doesn't contain any of those strings indeed it's still wrapped by advagg.