Examine source code of MDN Search

{
  "name": "MDN Code Search",
  "description": "To use, type 'mdn' plus your search term into the url bar.",
  "version": "1.1resigned1",
  "homepage_url": "https://github.com/clarkbw/mdn-code-search",
  "applications": {
    "gecko": {
      "strict_min_version": "52.0a1",
      "id": "{11bcf30b-c8f7-4685-b285-3944c02768af}"
    }
  },
  "icons": {
    "16": "icons/mdn-16.png",
    "48": "icons/mdn-48.png",
    "96": "icons/mdn-96.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "omnibox": {
    "keyword": "mdn"
  },
  "manifest_version": 2,
  "permissions": [
    "https://developer.mozilla.org/"
  ]
}