Examine source code of 1800's

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "1800's",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(162, 134, 96)",
      "toolbar_text": "rgb(36, 24, 12)",
      "frame": "rgb(161, 139, 112)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgba(210, 215, 205, 0.2)",
      "toolbar_field_text": "rgb(70, 59, 41)",
      "tab_line": "rgb(207, 164, 67)",
      "popup": "rgb(100, 81, 48)",
      "popup_text": "rgb(204, 151, 92)",
      "button_background_active": "rgb(174, 149, 117)",
      "button_background_hover": "rgb(142, 111, 72)",
      "icons_attention": "rgb(83, 58, 26)",
      "icons": "rgb(255, 255, 255)",
      "ntp_background": "rgb(161, 139, 112)",
      "ntp_text": "rgb(101, 71, 22)",
      "popup_border": "rgb(127, 105, 78)",
      "popup_highlight": "rgb(150, 109, 58)",
      "tab_loading": "rgb(207, 164, 67)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{fde61146-cd5f-493b-9fcd-911cc5ed2244}"
    }
  }
}