Examine source code of Knockout Inspect

{
  "manifest_version": 2,
  "name": "Knockout Inspect",
  "description": "An inspector for Knockout JS",
  "version": "0.0.1",
  "icons": {
    "64": "icons/icon-64.png",
    "128": "icons/icon-128.png",
    "512": "icons/icon-512.png"
  },
  "permissions": [
    "contextMenus"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content/script.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background/script.js"
    ]
  }
}