Examine source code of develov ubuntu

{
  "theme": {
    "images": {
      "theme_frame": "barfirefox_brushed2aaaaa.jpeg"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "develov ubuntu",
  "manifest_version": 2,
  "description": "my firefox"
}