Examine source code of FastNav

{
  "name": "FastNav",
  "description": "Quickly navigate to the next page with your keyboard. Press n to go to the next page, press p to go to the previous page.",
  "homepage_url": "https://github.com/Smile4ever/FastNav",
  "manifest_version": 3,
  "version": "1.4.0",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "128": "icons/fastnav-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "fastnav.js",
        "utils/keyutils.js"
      ],
      "run_at": "document_start"
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "permissions": [
    "tabs",
    "notifications",
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "fastnav@hugsmile.eu",
      "strict_min_version": "109.0"
    }
  }
}