Examine source code of Reset Page Zoom

{
  "name": "Reset Zoom",
  "version": "3.0",
  "description": "Reset the zoom of a page to 100%",
  "manifest_version": 2,
  "permissions": [
    "tabs",
    "activeTab",
    "menus",
    "contextMenus"
  ],
  "icons": {
    "48": "icon48.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {}
}