Examine source code of sel2in Web Notify Url

{
  "description": "Send current page URL to an web application's form.",
  "manifest_version": 2,
  "name": "sel2in_webExtnNotifyUrlWS",
  "version": "1.4resigned1",
  "homepage_url": "https://github.com/tgkprog/webExtnNotifyUrlWS",
  "icons": {
    "48": "res/icon1.png"
  },
  "applications": {
    "gecko": {
      "id": "sel2in_webExtnNotifyUrlWS@sel2in.com",
      "strict_min_version": "45.0"
    }
  },
  "options_ui": {
    "page": "op/options.html"
  },
  "permissions": [
    "activeTab",
    "tabs",
    "storage"
  ],
  "browser_action": {
    "default_icon": "res/icon1.png",
    "default_title": "Page Url Send"
  },
  "background": {
    "scripts": [
      "common.js",
      "notify.js"
    ]
  }
}