Examine source code of Activity Usage tracker

{
  "manifest_version": 3,
  "name": "WorldlineLog Browser Tracker",
  "version": "1.0.1",
  "description": "Captures lightweight browser activity and sends it to a local tracker.",
  "permissions": [
    "tabs",
    "activeTab",
    "scripting"
  ],
  "host_permissions": [
    "http://localhost:27777/*",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "activity-tracker@local",
      "data_collection_permissions": {
        "required": [
          "browsingActivity"
        ]
      }
    }
  }
}