Examine source code of Brown Note

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Brown Note",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-002-609370e89a219e0548ac5ef6b4a7dd2e.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(239, 237, 234, 0.84)",
      "toolbar_text": "rgb(108, 82, 85)",
      "frame": "rgb(193, 187, 182)",
      "tab_background_text": "rgb(108, 82, 85)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(108, 82, 85)",
      "tab_line": "rgb(108, 82, 85)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(108, 82, 85)",
      "button_background_active": "rgba(239, 237, 234, 0.84)",
      "button_background_hover": "rgb(108, 82, 85)",
      "icons_attention": "rgb(193, 187, 182)",
      "icons": "rgb(108, 82, 85)",
      "sidebar_text": "rgb(108, 82, 85)",
      "tab_background_separator": "rgb(50, 19, 21)",
      "tab_loading": "rgb(255, 255, 255)",
      "tab_selected": "rgb(108, 82, 85)",
      "tab_text": "rgba(239, 237, 234, 0.84)",
      "toolbar_bottom_separator": "rgb(110, 16, 22)",
      "toolbar_field_border_focus": "rgb(108, 82, 85)",
      "toolbar_field_border": "rgb(110, 16, 22)",
      "toolbar_field_focus": "rgb(255, 251, 251)",
      "toolbar_field_highlight_text": "rgba(239, 237, 234, 0.84)",
      "toolbar_field_highlight": "rgb(171, 101, 101)",
      "toolbar_field_separator": "rgb(110, 16, 22)",
      "toolbar_field_text_focus": "rgb(108, 82, 85)",
      "toolbar_top_separator": "rgb(110, 16, 22)",
      "toolbar_vertical_separator": "rgb(108, 82, 85)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3289a9f9-ee3d-48da-a66c-ea1c7b67a33e}"
    }
  }
}