Examine source code of No Cookie Wall

{
  "manifest_version": 2,
  "name": "No Cookie Wall",
  "version": "0.3.7",
  "description": "Remove the accept cookies or subscribe wall",
  "icons": {
    "16": "no-cookie-wall16.png",
    "48": "no-cookie-wall48.png",
    "128": "no-cookie-wall128.png"
  },
  "content_scripts": [
    {
      "js": [
        "paywall-detector.js"
      ],
      "css": [
        "style.css"
      ],
      "matches": [
        "https://*/*",
        "http://*/*"
      ]
    }
  ],
  "browser_action": {
    "default_icon": "no-cookie-wall48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{12aa14b2-5d1e-45ac-9554-bf4a5b427629}"
    }
  }
}