Examine source code of Winter 2009

{
  "theme": {
    "images": {
      "theme_frame": "ffskn4.png"
    },
    "colors": {
      "frame": "rgba(229,230,232,1)",
      "tab_background_text": "#0f2642"
    }
  },
  "version": "2.0",
  "name": "Winter 2009",
  "manifest_version": 2,
  "description": "A simple blue snowflake theme."
}