Examine source code of Page Translator v3

{
  "manifest_version": 2,
  "name": "Page Translator",
  "version": "1.0",
  "description": "Translate the current webpage into a selected language using Google Translate.",
  "icons": {
    "48": "icon.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1e31f967-aadf-4391-8ef4-b1f0b31b40c6}"
    }
  }
}