Examine source code of Datalayer Checker Plus

{
  "manifest_version": 2,
  "name": "Datalayer Checker",
  "short_name": "dlc",
  "version": "3.0.4",
  "author": "sublimetrix",
  "description": "The easiest way to debug and check the dataLayer implementations without having to use the browser console!",
  "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAu48MH2ynV1zcHs7GgECJ/IxkYAGbV8ZL6v5CQW4svTqgbgNh9RyhKgCxEOqqYZ8Zjy1h3ds5Mi+H6my0UPeLccTyng9P1yjE+VYgq8QepsfjH/fbFLulUnnGqmfIrHEWxjb4xcUtH3QopBxuw9vuMSlij26J/FLP2YJnfXUp2KL0JWCKSHECoNambLxKHRM1exbgzQ+d1reFuaNmMYKGYMBEE4AqN7QIMuc4HF7A2w9rIHgfhb6F+d787p7jbZfI1T1GgLgS76I8ncdh+VP28VemA7/GaWE8eskp+LHHujmJnMaIRoHrfIvLQan2vkZIkMZ3SnmIh2siGCRJZPvuqwIDAQAB",
  "permissions": [
    "activeTab",
    "storage",
    "http://*/*",
    "https://*/*",
    "https://umami.datalayerchecker.com/*"
  ],
  "web_accessible_resources": [
    "js/datalayer-checker.js"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "64": "icons/icon64.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon48.png",
    "48": "icons/icon48.png",
    "64": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "background": {
    "scripts": [
      "service_worker.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b87058b6-f88b-47c1-8e71-49bd8ce32b66}"
    }
  }
}