Examine source code of Afternight

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Afternight",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg",
        "images/1.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center top",
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "repeat",
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(76, 0, 128)",
      "toolbar_text": "rgb(232, 179, 255)",
      "frame": "rgb(50, 0, 86)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(55, 55, 55)",
      "toolbar_field_text": "rgb(236, 194, 255)",
      "tab_line": "rgb(128, 0, 255)",
      "popup": "rgb(50, 0, 86)",
      "popup_text": "rgb(212, 121, 255)",
      "tab_loading": "rgb(128, 0, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6f271972-6597-4332-a23f-6e1c0a9d5c70}"
    }
  }
}