Examine source code of Sink It for Reddit

{
  "manifest_version": 2,
  "default_locale": "en",
  "name": "Sink It for Reddit",
  "description": "Improve your Reddit experience.",
  "version": "8.6.0",
  "icons": {
    "48": "images/logo-48x48.png",
    "96": "images/logo-96x96.png",
    "128": "images/logo-128x128.png",
    "256": "images/logo-256x256.png"
  },
  "background": {
    "scripts": [
      "env.js",
      "browser-polyfill.min.js",
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "*://reddit.com/*",
        "*://www.reddit.com/*",
        "*://sh.reddit.com/*",
        "*://old.reddit.com/*",
        "*://new.reddit.com/*"
      ],
      "js": [
        "env.js",
        "browser-polyfill.min.js",
        "gungnir.js",
        "prometheus.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "options_ui": {
    "page": "dist/index.html"
  },
  "browser_action": {
    "default_title": "Sink It for Reddit",
    "default_popup": "dist/index.html",
    "default_icon": {
      "16": "images/logo-16x16.png",
      "19": "images/logo-19x19.png",
      "32": "images/logo-32x32.png",
      "38": "images/logo-38x38.png"
    }
  },
  "permissions": [
    "activeTab",
    "tabs",
    "storage"
  ],
  "gecko": {
    "id": "{09acf9ff-55d4-4366-a1a9-c9b3c8877c09}"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{09acf9ff-55d4-4366-a1a9-c9b3c8877c09}"
    }
  }
}