Examine source code of Mustsee

{
  "manifest_version": 2,
  "name": "Mustsee",
  "version": "1.86resigned1",
  "description": "Discover the world's most beautiful places at every opened tab.",
  "homepage_url": "http://mustsee.earth",
  "strict_min_version": "53.0",
  "author": "Mustsee",
  "icons": {
    "16": "icons/icon16.png",
    "19": "icons/icon19.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "developer": {
    "name": "Mustsee",
    "url": "http://mustsee.earth"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d902cd07-63c2-48bd-937b-1622308a3cd1}"
    }
  }
}