Examine source code of Adwaita Borderless Darker

{
  "manifest_version": 2,
  "version": "1.31",
  "name": "Adwaita Borderless Darker",
  "author": "Dobbie03",
  "description": "Unified simple dark theme that removes borders. A darker version.",
  "homepage_url": "https://github.com/Dobbie03/adwaita_borderless_dark",
  "icons": {
    "16": "icon-16.png",
    "48": "icon-48.png",
    "96": "icon-96.png",
    "128": "icon-128.png"
  },
  "theme": {
    "colors": {
      "bookmark_text": "#c6c6c6",
      "button_background_active": "#141414",
      "button_background_hover": "#141414",
      "frame_inactive": "#141414",
      "frame": "#141414",
      "icons_attention": "#c6c6c6",
      "icons": "#c6c6c6",
      "ntp_background": "#141414",
      "ntp_card_background": "#212121",
      "ntp_text": "#c6c6c6",
      "popup_border": "#141414",
      "popup_highlight_text": "#c6c6c6",
      "popup_highlight": "#303030",
      "popup_text": "#c6c6c6",
      "popup": "#141414",
      "sidebar_border": "#141414",
      "sidebar_highlight_text": "rgba(129, 162, 190, 0.6)",
      "sidebar_highlight": "#212121",
      "sidebar_text": "#c6c6c6",
      "sidebar": "#141414",
      "tab_background_text": "#a9a9ab",
      "tab_line": "#141414",
      "tab_loading": "#c6c6c6",
      "tab_selected": "#141414",
      "tab_text": "#fffefe",
      "toolbar_bottom_separator": "#141414",
      "toolbar_field_border_focus": "#141414",
      "toolbar_field_border": "#141414",
      "toolbar_field_focus": "#212121",
      "toolbar_field_highlight_text": "#808fa0",
      "toolbar_field_highlight": "#141414",
      "toolbar_field_text_focus": "#c6c6c6",
      "toolbar_field_text": "#808fa0",
      "toolbar_field": "#141414",
      "toolbar_top_separator": "#141414",
      "toolbar_vertical_separator": "#141414",
      "toolbar": "#141414"
    },
    "properties": {
      "color_scheme": "dark",
      "content_color_scheme": "dark"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d42afa76-b8e0-468a-a5e7-e6cf6bc646d6}"
    }
  }
}