Examine source code of Page Keep-Alive

{
  "manifest_version": 3,
  "name": "Page Keep-Alive",
  "version": "1.6.0",
  "description": "Keeps pages active when switching between windows",
  "permissions": [
    "storage",
    "tabs",
    "activeTab"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon-off-16.png",
      "32": "icon-off-32.png"
    },
    "default_title": "Page Keep-Alive"
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6c4d1833-829a-42b4-8525-cb7962a28e84}",
      "strict_min_version": "109.0"
    }
  }
}