Examine source code of 49ers

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#a80000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "49ers",
  "manifest_version": 2,
  "description": "SF 49ers Gold Blooded. Includes images from <a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/4826ee9313048c1182d8e069068e176c7735d10c7521b86c78c0d9c04d585181/http%3A//49ers.com\">49ers.com</a> candlestick park and levi's stadium."
}