Examine source code of Metasearch

{
  "author": "Rafael Ketsetsides",
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "61.0",
      "id": "{636dd0cd-a140-44ff-b319-3bc70fbdb486}"
    }
  },
  "icons": {
    "16": "img/icon16.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "background": {
    "scripts": [
      "browser-polyfill.min.js",
      "background.js"
    ]
  },
  "description": "Metasearch is a search engine aggregator.",
  "manifest_version": 2,
  "name": "Metasearch",
  "options_ui": {
    "page": "options.html"
  },
  "permissions": [
    "tabs",
    "tabHide",
    "storage",
    "webRequest",
    "contextMenus",
    "<all_urls>"
  ],
  "chrome_settings_overrides": {
    "search_provider": {
      "name": "Metasearch",
      "search_url": "https://metasearch/?q={searchTerms}",
      "favicon_url": "img/icon.svg"
    }
  },
  "browser_action": {
    "default_icon": {
      "16": "img/icon16.png",
      "24": "img/icon24.png",
      "32": "img/icon32.png"
    },
    "default_title": "Metasearch"
  },
  "version": "1.3.7"
}