Examine source code of red2black2

{
  "theme": {
    "images": {
      "theme_frame": "d5.PNG"
    },
    "colors": {
      "frame": "#c40000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "red2black2",
  "manifest_version": 2,
  "description": "from red to black"
}