Examine source code of Low Poly (Dark Red)

{
  "manifest_version": 2,
  "version": "12.0",
  "name": "Low Poly (Dark Red)",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(0, 0, 0, 0.1)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(52, 0, 0)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgba(0, 0, 0, 0)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgba(240, 20, 20, 0.9)",
      "popup": "rgba(59, 0, 0, 0.98)",
      "popup_text": "rgb(255, 255, 255)",
      "button_background_active": "rgb(173, 0, 0)",
      "button_background_hover": "rgba(79, 0, 0, 0.85)",
      "frame_inactive": "rgb(255, 110, 110)",
      "icons_attention": "rgb(226, 5, 5)",
      "icons": "rgb(255, 255, 255)",
      "ntp_background": "rgb(52, 0, 0)",
      "ntp_text": "rgb(255, 255, 255)",
      "popup_border": "rgba(56, 0, 0, 0.98)",
      "popup_highlight_text": "rgb(255, 255, 255)",
      "popup_highlight": "rgb(115, 0, 0)",
      "sidebar_border": "rgb(38, 0, 0)",
      "sidebar_highlight_text": "rgb(255, 255, 255)",
      "sidebar_highlight": "rgb(150, 0, 0)",
      "sidebar_text": "rgb(255, 255, 255)",
      "sidebar": "rgb(38, 0, 0)",
      "tab_background_separator": "rgba(215, 47, 47, 0)",
      "tab_loading": "rgb(255, 0, 0)",
      "tab_selected": "rgba(72, 0, 0, 0.41)",
      "tab_text": "rgba(255, 255, 255, 0.85)",
      "toolbar_bottom_separator": "rgba(0, 0, 0, 0)",
      "toolbar_field_border_focus": "rgb(175, 0, 0)",
      "toolbar_field_border": "rgba(202, 0, 0, 0)",
      "toolbar_field_focus": "rgba(56, 0, 0, 0.98)",
      "toolbar_field_highlight_text": "rgb(255, 255, 255)",
      "toolbar_field_highlight": "rgb(204, 0, 0)",
      "toolbar_field_text_focus": "rgb(255, 255, 255)",
      "toolbar_top_separator": "rgba(91, 0, 0, 0)",
      "toolbar_vertical_separator": "rgb(153, 87, 87)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0ae6ff54-9b9d-4422-bec1-c57c70de3874}"
    }
  }
}