Examine source code of Translate Text Selected

{
  "manifest_version": 2,
  "name": "Translate Selection",
  "version": "0.3",
  "description": "Automatically translate selected text",
  "icons": {
    "128": "icons/logo.png"
  },
  "browser_action": {
    "default_title": "Translate Selection",
    "default_icon": {
      "128": "icons/logo.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "assets/js/translate.js"
      ],
      "css": [
        "assets/css/styles.css"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "contextMenus",
    "clipboardWrite",
    "webRequest",
    "notifications",
    "alarms",
    "find",
    "activeTab",
    "search",
    "browserSettings",
    "webNavigation",
    "*://translate.googleapis.com/*"
  ]
}