Examine source code of Pixel Tiles

{
  "theme": {
    "images": {
      "theme_frame": "pixborder.png"
    },
    "colors": {
      "frame": "#1a1a1a",
      "tab_background_text": "#1a1a1a"
    }
  },
  "version": "2.0",
  "name": "Pixel Tiles",
  "manifest_version": 2,
  "description": "pattern from\n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/cc56790c03dbcea4d0dd2bab71467de3edccf40c67a1d5aca1588914cc587852/http%3A//www.k10k.net/pixelpatterns/\">http://www.k10k.net/pixelpatterns/</a>"
}