Examine source code of Todoist NewTab

{
  "manifest_version": 2,
  "name": "Todoist NewTab",
  "version": "1.0",
  "description": "Simple displays of Todoist tasks when opening a new tab",
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "yapakema@gmail.com"
    }
  },
  "permissions": [
    "https://api.todoist.com/*",
    "storage"
  ],
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png"
    },
    "default_title": "Todoist New Tab",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  }
}