Examine source code of blinklight

{
  "name": "blinklight",
  "version": "2.3resigned1",
  "description": "LED notification of urgent tabs on Linux",
  "homepage_url": "https://github.com/snoack/chrome-blinklight",
  "permissions": [
    "tabs",
    "storage",
    "webNavigation",
    "nativeMessaging",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "led.js",
      "blinklight.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "chrome_style": true
  },
  "icons": {
    "32": "icon-32.png",
    "128": "icon-128.png"
  },
  "minimum_chrome_version": "42",
  "manifest_version": 2,
  "applications": {
    "gecko": {
      "id": "blinklight@snoack.addons.mozilla.org",
      "strict_min_version": "50.0"
    }
  },
  "key": "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCprfGX9/itvOCSKlq82T3+YW6kuO/kuggH6AniK3tvfYz+pa4RFOLWxf7q60zWF3uYKzpJj2O3/zmH6FrjGy+cxWDvrChH4c45eTTZNC99l9Xz8/FBsupQHYUBP2FUiLnJ5eHAgAPjSOnAUQSfy+Jhi6fRCpTXX1bPQ8S4Henq4QIDAQAB"
}