Examine source code of Red Hot

{
  "theme": {
    "images": {
      "theme_frame": "Red_Hot_H.jpg"
    },
    "colors": {
      "frame": "#ff0000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Red Hot",
  "manifest_version": 2,
  "description": "A simple glowy red streak, lined up with the top of the address bar (bottom on Mac). Good if you don't like clutter up there."
}