Examine source code of Jomo Companion

{
  "manifest_version": 3,
  "name": "Jomo Companion",
  "version": "1.0.9",
  "description": "Companion extension for Jomo.",
  "browser_specific_settings": {
    "gecko": {
      "id": "jomo-companion@jomo.so"
    }
  },
  "permissions": [
    "webNavigation",
    "nativeMessaging"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ]
}