Examine source code of Swift Translate Selected

{
  "manifest_version": 2,
  "name": "Swift Translate Selected",
  "version": "1.0",
  "description": "Translates selected text in a new window swiftly",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "48": "Icon.png"
  },
  "permissions": [
    "menus"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://translate.google.com/*"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{130c8d64-0722-410e-bbfd-6f2042f2b01c}"
    }
  }
}