Examine source code of Rainbow Gradient Splatter

{
  "theme": {
    "images": {
      "theme_frame": "rainbowabstractpersonacopy.jpg"
    },
    "colors": {
      "frame": "rgba(229,230,232,1)",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Rainbow Gradient Splatter",
  "manifest_version": 2,
  "description": "***Brush credit: <a href=\"https://outgoing.prod.mozaws.net/v1/b77c0bc4cec50e7f20f7d9e2a258d7e47cd8166df89526c630cc852b6bc31d91/http%3A//Obsidiandawn.com\" rel=\"nofollow\">Obsidiandawn.com</a>***\nJust a rainbow gradient with some designs..."
}