src/content_scripts/thread_inject.js

var CCRegex = /^https:\/\/support\.google\.com\/s\/community/;
if (!CCRegex.test(location.href)) {
  var intersectionObserver;

  function intersectionCallback(entries, observer) {
    entries.forEach(entry => {
      if (entry.isIntersecting) {
        entry.target.click();
      }
    });
  };

  var intersectionOptions = {
    threshold: 1.0,
  };

  chrome.storage.sync.get(null, function(items) {
    var path = document.location.pathname.split('/');
    if (path[path.length - 1] == 'new' ||
        (path.length > 1 && path[path.length - 1] == '' &&
         path[path.length - 2] == 'new')) {
      return;
    }

    var redirectLink = document.querySelector('.community-console');
    if (items.redirect && redirectLink !== null) {
      window.location = redirectLink.href;
    } else {
      var button =
          document.querySelector('.thread-all-replies__load-more-button');
      if (items.thread && button !== null) {
        intersectionObserver =
            new IntersectionObserver(intersectionCallback, intersectionOptions);
        intersectionObserver.observe(button);
      }
      var allbutton =
          document.querySelector('.thread-all-replies__load-all-button');
      if (items.threadall && button !== null) {
        intersectionObserver =
            new IntersectionObserver(intersectionCallback, intersectionOptions);
        intersectionObserver.observe(allbutton);
      }

      if (items.profileindicator) {
        injectScript(
            chrome.runtime.getURL('injections/profileindicator_inject.js'));
        injectStylesheet(
            chrome.runtime.getURL('injections/profileindicator_inject.css'));

        // In order to pass i18n strings to the injected script, which doesn't
        // have access to the chrome.i18n API.
        window.addEventListener('geti18nString', evt => {
          var request = evt.detail;
          var response = {
            string: chrome.i18n.getMessage(request.msg),
            requestId: request.id
          };
          window.dispatchEvent(
              new CustomEvent('sendi18nString', {detail: response}));
        });
      }
    }
  });
}