Examine source code of PushToReader

{
  "manifest_version": 3,
  "name": "PushToReader",
  "version": "1.0.6",
  "description": "Send articles to your e-reader with one click",
  "permissions": [
    "activeTab",
    "scripting",
    "storage"
  ],
  "host_permissions": [
    "https://api.pushtoreader.com/*"
  ],
  "action": {
    "default_popup": "./popup/popup.html",
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    }
  },
  "background": {
    "scripts": [
      "./background.bundle.js"
    ]
  },
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "pushtoreader@pushtoreader.com",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "websiteActivity",
          "websiteContent"
        ]
      }
    }
  }
}