Examine source code of Heureca!

{
  "name": "Heureca!",
  "short_name": "Heureca",
  "description": "The shortcut to Mystery Cache Solutions. Enriches geocaching.com with a set of tools for decryption and working with coordinates.",
  "manifest_version": 2,
  "minimum_chrome_version": "30.0",
  "version": "0.0.100resigned1",
  "icons": {
    "16": "images/heureca16.png",
    "48": "images/heureca48.png",
    "128": "images/heureca128.png"
  },
  "default_locale": "en",
  "page_action": {
    "default_icon": {
      "19": "images/heureca19.png",
      "48": "images/heureca48.png"
    },
    "default_popup": "popup_compiled.html",
    "default_title": "Heureca!"
  },
  "background": {
    "scripts": [
      "background_compiled.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "http://www.geocaching.com/*",
        "https://www.geocaching.com/*",
        "http://www.opencaching.com/*",
        "https://www.opencaching.com/*",
        "http://www.opencaching.de/*",
        "https://www.opencaching.de/*",
        "http://www.opencaching.pl/*",
        "https://www.opencaching.pl/*",
        "http://www.opencaching.se/*",
        "https://www.opencaching.se/*",
        "http://www.opencaching.no/*",
        "https://www.opencaching.no/*",
        "http://www.opencaching.ro/*",
        "https://www.opencaching.ro/*",
        "http://www.opencaching.nl/*",
        "https://www.opencaching.nl/*",
        "http://www.opencaching.us/*",
        "https://www.opencaching.us/*",
        "http://www.opencaching.ca/*",
        "https://www.opencaching.ca/*",
        "http://www.opencaching.mx/*",
        "https://www.opencaching.mx/*",
        "http://www.opencaching.it/*",
        "https://www.opencaching.it/*",
        "http://www.opencaching.es/*",
        "https://www.opencaching.es/*",
        "http://www.opencaching.org.uk/*",
        "https://www.opencaching.org.uk/*",
        "http://www.opencaching.cz/*",
        "https://www.opencaching.cz/*",
        "http://www.gccheck.com/*",
        "https://www.gccheck.com/*",
        "http://www.gc-apps.com/*",
        "https://www.gc-apps.com/*",
        "http://geochecker.com/*",
        "https://geochecker.com/*",
        "http://www.geochecker.com/*",
        "https://www.geochecker.com/*",
        "http://geocheck.org/*",
        "https://geocheck.org/*",
        "http://www.geocheck.org/*",
        "https://www.geocheck.org/*",
        "http://evince.locusprime.net/*",
        "https://evince.locusprime.net/*",
        "http://geochecker.gps-cache.de/*",
        "https://geochecker.gps-cache.de/*",
        "https://www.geocheck.org/*",
        "http://geotjek.dk/*",
        "https://geotjek.dk/*",
        "https://www.geotjek.dk/*",
        "http://www.geotjek.dk/*",
        "http://www.heureca.de/*",
        "https://www.heureca.de/*",
        "http://www.heureca.net/*",
        "https://www.heureca.net/*"
      ],
      "js": [
        "analytics.js",
        "latlng.js",
        "math.min.js",
        "material.min.js",
        "heureca.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "images/*",
    "css/*",
    "firebase.js",
    "latlng.js",
    "material.min.js",
    "material.min.js.map"
  ],
  "oauth2": {
    "client_id": "866331598230-mr44tikp9klpsdfjcct7fv1gl9m4hlqp.apps.googleusercontent.com",
    "scopes": [
      "https://www.googleapis.com/auth/userinfo.profile",
      "https://www.googleapis.com/auth/drive"
    ]
  },
  "permissions": [
    "contextMenus",
    "identity",
    "storage",
    "tabs"
  ],
  "optional_permissions": [
    "clipboardRead",
    "clipboardWrite"
  ],
  "applications": {
    "gecko": {
      "id": "firefox-addon-v1@heureca.net",
      "strict_min_version": "42.0"
    }
  }
}