Examine source code of R31GN's Custom Theme

{
  "name": "R31GN's Custom Theme",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "CraftyCircularBeauceron-max-1mb.gif"
    },
    "colors": {
      "frame": "rgba(255, 0, 0, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{244f3669-5912-44e2-bc9d-2ab5d8bc1925}"
    }
  }
}