gecko-dev/toolkit/content/aboutRights.js

var servicesDiv = document.getElementById("webservices-container");
servicesDiv.style.display = "none";

function showServices() {
  servicesDiv.style.display = "";
}

// Fluent replaces the children of the element being overlayed which prevents us
// from putting an event handler directly on the children.
let rightsIntro = document.querySelector("[data-l10n-id=rights-intro-point-5]") ||
                  document.querySelector("[data-l10n-id=rights-intro-point-5-unbranded]");
rightsIntro.addEventListener("click", event => {
  if (event.target.id == "showWebServices") {
    showServices();
  }
});

var disablingServicesDiv = document.getElementById("disabling-webservices-container");

function showDisablingServices() {
  disablingServicesDiv.style.display = "";
}

if (disablingServicesDiv != null) {
  disablingServicesDiv.style.display = "none";
  // Same issue here with Fluent replacing the children affecting the event listeners.
  let rightsWebServices = document.querySelector("[data-l10n-id=rights-webservices]");
  rightsWebServices.addEventListener("click", event => {
    if (event.target.id == "showDisablingWebServices") {
      showDisablingServices();
    }
  });
}