Examine source code of ARCTracker

{
  "manifest_version": 3,
  "name": "ARCTracker",
  "version": "1.0.1",
  "description": "Links your Embark account to ARCTracker for automatic sync",
  "browser_specific_settings": {
    "gecko": {
      "id": "arctracker@arctracker.io",
      "strict_min_version": "130.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "declarativeNetRequest",
    "declarativeNetRequestWithHostAccess"
  ],
  "host_permissions": [
    "http://127.0.0.1/*",
    "http://localhost/*",
    "https://*.arctracker.io/*",
    "https://arctracker.io/*"
  ],
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "ruleset_1",
        "enabled": true,
        "path": "rules.json"
      }
    ]
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.arctracker.io/*",
        "https://arctracker.io/*",
        "http://localhost/*"
      ],
      "js": [
        "presence.js"
      ],
      "run_at": "document_start"
    }
  ],
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  }
}