Examine source code of browser-reader-alpha

{
  "manifest_version": 3,
  "version": "0.3.1",
  "name": "Scroll",
  "description": "An automatic scrolling reader for comfortable reading of long web pages",
  "browser_specific_settings": {
    "gecko": {
      "id": "scroll-alpha@example.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "activeTab",
    "scripting",
    "storage",
    "tabs"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "action": {
    "default_icon": {
      "48": "icons/reader-48.png"
    },
    "default_title": "Toggle Scroll",
    "default_popup": "popup.html"
  },
  "icons": {
    "48": "icons/reader-48.png"
  },
  "commands": {
    "toggle-reader": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y",
        "mac": "Command+Shift+Y"
      },
      "description": "Toggle Scroll on/off"
    }
  }
}