Examine source code of Focused Dev Mode

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Dev Mode",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-016-af8c49de75012ca2c007f953ff2e4499.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(0, 0, 0, 0.86)",
      "toolbar_text": "rgb(115, 228, 47)",
      "frame": "rgb(3, 16, 3)",
      "tab_background_text": "rgb(184, 228, 47)",
      "toolbar_field": "rgb(19, 19, 19)",
      "toolbar_field_text": "rgb(195, 204, 157)",
      "tab_line": "rgb(0, 0, 0)",
      "popup": "rgb(19, 19, 19)",
      "popup_text": "rgb(115, 228, 47)",
      "frame_inactive": "rgb(0, 0, 0)",
      "icons_attention": "rgb(235, 68, 229)",
      "ntp_background": "rgb(0, 0, 0)",
      "popup_border": "rgb(0, 0, 0)",
      "popup_highlight": "rgb(166, 70, 224)",
      "sidebar_border": "rgb(0, 0, 0)",
      "sidebar_highlight": "rgb(184, 228, 47)",
      "sidebar": "rgb(214, 250, 88)",
      "tab_loading": "rgb(166, 70, 224)",
      "tab_text": "rgb(115, 228, 47)",
      "toolbar_bottom_separator": "rgb(235, 68, 229)",
      "toolbar_field_border": "rgb(0, 0, 0)",
      "toolbar_field_highlight_text": "rgb(235, 68, 229)",
      "toolbar_vertical_separator": "rgb(235, 68, 229)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dd781d0d-06f5-43f8-9506-add48ecdfadf}"
    }
  }
}