Examine source code of Planet View

{
  "manifest_version": 2,
  "name": "Planet View",
  "description": "Planet View displays a beautiful satellite image from Planet every time you open a new tab.",
  "version": "2.6.0",
  "icons": {
    "16": "assets/images/icon-16.png",
    "48": "assets/images/icon-48.png",
    "128": "assets/images/icon-128.png"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "incognito": "not_allowed"
}