Examine source code of Save to Screenly

{
  "manifest_version": 3,
  "name": "Save to Screenly",
  "version": "1.6.0",
  "description": "Display live web pages on your Screenly digital sign.",
  "icons": {
    "16": "assets/images/screenly-logo-16.png",
    "48": "assets/images/screenly-logo-48.png",
    "128": "assets/images/screenly-logo-128.png"
  },
  "permissions": [
    "activeTab",
    "storage",
    "scripting",
    "cookies"
  ],
  "host_permissions": [
    "http://*/*",
    "https://*/*"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_title": "Save to Screenly",
    "default_icon": {
      "16": "assets/images/screenly-logo-16.png",
      "32": "assets/images/screenly-logo-32.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "addon@screenly.io",
      "strict_min_version": "60.0"
    }
  }
}