Examine source code of Fractal whisper

{
  "theme": {
    "images": {
      "theme_frame": "null-15.jpg"
    },
    "colors": {
      "frame": "#3d0b21",
      "tab_background_text": "#fafaf7"
    }
  },
  "version": "2.0",
  "name": "Fractal whisper",
  "manifest_version": 2,
  "description": "Fractal art by Helene Kippert"
}