Examine source code of put.io

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "2.3.3",
  "default_locale": "en",
  "applications": {
    "gecko": {
      "id": "{1edc8157-02d9-460b-9305-b31a5b713d9d}"
    }
  },
  "homepage_url": "https://github.com/putdotio/putio-webextension",
  "key": "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCBY/vZ2HE8Vul6TqZA+q/c5ZLEWLWkk4Cd5tz5RHBi2DqMvty/evWUtQgZ3XVDKLGAA+KU1YYDc9UKR4WJ+UBmIos+rJHKWl/gm4ClCn2EUsAk3JtucexhFFc6DZzMCyH+ZAn5103eCozVCYV6C+9HDrgeBJyRc8HIDDy2i+mAzwIDAQAB",
  "permissions": [
    "tabs",
    "contextMenus",
    "identity",
    "storage",
    "notifications"
  ],
  "browser_action": {
    "default_icon": "icon.png"
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "background": {
    "scripts": [
      "browser-polyfill.js",
      "background.js"
    ]
  }
}