How to add variables in *.libraries.yml in drupal 8
First add your acobot script inline:

function mymodule_page_attachments(array &amp;$attachments) {
  $attachments['#attached']['html_head'][] = [
    // The data.
    [
      '#type' =&gt; 'html_tag',
      // The HTML tag to add, in this case a  tag.
      '#tag' =&gt; 'script',
      // The value of the HTML tag, here we want to end up with
      // alert("Hello world!");.
      '#value' =&gt; 'alert("Hello world!");',
      // Set attributes like src to load a file.
      '#attributes' =&gt; array('src' =&gt; 'http://js.acobot.com/' . check_plain($token) . '.js'),

    ],
    // A key, to make it possible to recognize this HTML  element when altering.
    'hello-world',
  ];
}


next add your library with *.js file where you can call push method 

cuddly-slider:
  version: 1.x
  js:
    js/cuddly-slider.js: {}
  dependencies:
    - core/jquery
    - core/drupalSettings


and pass user mail to  drupalSettings.

$build['#attached']['drupalSettings']['fluffiness']['cuddlySlider']['foo'] = 'user mail here';


All examples are available here https://www.drupal.org/docs/8/creating-custom-modules/adding-stylesheets-css-and-javascript-js-to-a-drupal-8-module