Examine source code of Switch - Search With

{
  "manifest_version": 2,
  "name": "Switch - Search With",
  "version": "1.1",
  "description": "Adds a \"Search with (search engine)\" button when you right-click highlighted text!",
  "background": {
    "scripts": [
      "main.js"
    ]
  },
  "permissions": [
    "menus",
    "search"
  ],
  "icons": {
    "48": "icons/icon.svg",
    "96": "icons/icon.svg"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2730af29-f323-4d5f-89f7-57c5368b4c2c}"
    }
  }
}