Examine source code of xkcd New Tab

{
  "description": "Displays the latest xkcd comic in your new tab.",
  "manifest_version": 2,
  "name": "xkcd New Tab",
  "version": "1.0.1",
  "homepage_url": "https://github.com/chr1s-b/xkcd-new-tab",
  "icons": {
    "48": "icons/icon_48.png"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "permissions": [
    "*://xkcd.com/info.0.json",
    "webRequest"
  ]
}