Extract completed tasks from open Trello card using JavaScript and jQuery

tasks.js

const tasks = () => {
  let tasks = ``;
  // eslint-disable-next-line
  $.each( $('.checklist-item-state-complete'), (i, val) => { // jQuery is already loaded by Trello
    const task = $(val).find('.js-checkitem-name').text(); // eslint-disable-line
    tasks = `${tasks}\n${task}`;
  });
  tasks = `${tasks}\n`;
  return tasks;
};

// pro tip: use with Chrome plugin like GreaseMonkey or Tampermonkey to avoid manually re-typing function on website reload