Examine source code of Ninja Strokes

{
  "theme": {
    "images": {
      "theme_frame": "NinjaStrokesPersona.png"
    },
    "colors": {
      "frame": "#545454",
      "tab_background_text": "#bfbfbf"
    }
  },
  "version": "2.0",
  "name": "Ninja Strokes",
  "manifest_version": 2,
  "description": "Ninja like stroke pattern on this very simple design."
}