Examine source code of Test Pilot Dark

{
  "manifest_version": 2,
  "version": "2.0",
  "name": "Test pilot dark",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(255, 255, 255, 0)",
      "toolbar_text": "rgb(238, 238, 238)",
      "frame": "rgb(43, 43, 52)",
      "tab_background_text": "rgb(221, 221, 221)",
      "toolbar_field": "rgb(68, 68, 79)",
      "toolbar_field_text": "rgb(238, 238, 238)",
      "tab_line": "rgb(133, 133, 155)",
      "popup": "rgb(43, 43, 52)",
      "popup_text": "rgb(238, 238, 238)",
      "tab_loading": "rgb(133, 133, 155)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b5d902e1-a891-4b5a-a6b8-d5da923da9fc}"
    }
  }
}