Examine source code of On Thine Pen

{
  "theme": {
    "images": {
      "theme_frame": "header.jpg"
    },
    "colors": {
      "frame": "#11032b",
      "tab_background_text": "#5c0587"
    }
  },
  "version": "2.0",
  "name": "On Thine Pen",
  "manifest_version": 2,
  "description": "writing dark stripes doth I write pen ink"
}