Examine source code of Neon Sketch

{
  "theme": {
    "images": {
      "theme_frame": "firefox2.jpg"
    },
    "colors": {
      "frame": "#0076de",
      "tab_background_text": "#46b0fc"
    }
  },
  "version": "2.0",
  "name": "Neon Sketch",
  "manifest_version": 2,
  "description": "Its my first this style creation. I used GIMP to make it. I will make more if this one is liked :)"
}