Examine source code of playinnowbot

{
  "manifest_version": 2,
  "version": "1.0.3",
  "name": "playinnowbot",
  "description": "Extension for secure authorization of playinnowbot users in Telegram",
  "icons": {
    "16": "images/logo16.png",
    "32": "images/logo32.png",
    "48": "images/logo48.png",
    "128": "images/logo128.png",
    "1080": "images/logo1080.png"
  },
  "permissions": [
    "tabs",
    "storage",
    "cookies",
    "https://soundcloud.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "browser_style": true,
    "default_popup": "popup/popup.html",
    "default_title": "playinnowbot | Authorization"
  },
  "applications": {
    "gecko": {
      "id": "playinnowbot@es3n1n.eu"
    }
  }
}