Examine source code of Developer UX

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Developer UX",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(0, 26, 41)",
      "toolbar_text": "rgb(254, 254, 254)",
      "frame": "rgb(0, 12, 18)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(78, 206, 0)",
      "tab_line": "rgb(247, 255, 0)",
      "popup": "rgb(228, 228, 228)",
      "popup_text": "rgb(0, 3, 5)",
      "button_background_active": "rgba(247, 255, 0, 0.6)",
      "button_background_hover": "rgb(255, 255, 255)",
      "frame_inactive": "rgb(255, 255, 255)",
      "icons_attention": "rgb(255, 255, 255)",
      "icons": "rgb(255, 124, 0)",
      "ntp_text": "rgb(255, 255, 255)",
      "popup_border": "rgb(255, 138, 0)",
      "popup_highlight_text": "rgb(255, 255, 255)",
      "popup_highlight": "rgb(0, 255, 204)",
      "sidebar_border": "rgb(255, 139, 0)",
      "sidebar_highlight_text": "rgb(0, 0, 0)",
      "sidebar_highlight": "rgba(255, 255, 0, 0.6)",
      "sidebar_text": "rgb(255, 255, 255)",
      "tab_background_separator": "rgb(0, 0, 0)",
      "tab_loading": "rgb(255, 255, 255)",
      "tab_selected": "rgba(0, 0, 0, 0.5)",
      "tab_text": "rgb(243, 247, 247)",
      "toolbar_bottom_separator": "rgb(255, 241, 1)",
      "toolbar_field_border_focus": "rgb(255, 255, 255)",
      "toolbar_field_border": "rgb(255, 252, 222)",
      "toolbar_field_focus": "rgb(37, 37, 37)",
      "toolbar_field_highlight_text": "rgb(250, 228, 1)",
      "toolbar_field_highlight": "rgb(83, 83, 83)",
      "toolbar_field_separator": "rgb(255, 255, 255)",
      "toolbar_field_text_focus": "rgb(0, 193, 162)",
      "toolbar_top_separator": "rgb(255, 152, 0)",
      "toolbar_vertical_separator": "rgb(255, 241, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f97a4ca8-bb07-42af-9345-2e4985df4c99}"
    }
  }
}