Examine source code of Frequency Radio

{
  "manifest_version": 3,
  "name": "Frequency",
  "version": "1.1.0",
  "description": "Minimalist Belgian Radio Player",
  "permissions": [
    "storage",
    "offscreen"
  ],
  "host_permissions": [
    "https://*.vrtcdn.be/*",
    "https://*.streamtheworld.com/*",
    "https://*.triple-it.nl/*",
    "https://*.radio.dpgmedia.cloud/*",
    "https://*.vrt.be/*"
  ],
  "background": {
    "type": "module",
    "scripts": [
      "service-worker-loader.js"
    ]
  },
  "action": {
    "default_popup": "index.html",
    "default_icon": {
      "16": "frequency_icon.png",
      "48": "frequency_icon.png",
      "128": "frequency_icon.png"
    }
  },
  "icons": {
    "16": "frequency_icon.png",
    "48": "frequency_icon.png",
    "128": "frequency_icon.png"
  },
  "web_accessible_resources": [
    {
      "matches": [
        "<all_urls>"
      ],
      "resources": [
        "src/offscreen/offscreen.html"
      ],
      "use_dynamic_url": false
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "frequency-radio-be@addons.mozilla.org",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}