Examine source code of Tabbable Search

{
  "manifest_version": 2,
  "name": "Tabbable Search",
  "version": "1.0",
  "description": "In the Google search results page, allow the tab key (and shift-tab key) to jump from item to item.",
  "icons": {
    "48": "icon.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.google.com/search?*"
      ],
      "js": [
        "google.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{34f9333c-d5ee-45c7-a70c-b9bc80df4010}"
    }
  }
}