Examine source code of nightfall

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "nightfall",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(32, 35, 37)",
      "toolbar_text": "rgb(215, 226, 239)",
      "frame": "rgb(24, 26, 27)",
      "tab_background_text": "rgb(215, 226, 239)",
      "toolbar_field": "rgb(24, 26, 27)",
      "toolbar_field_text": "rgb(215, 226, 239)",
      "tab_line": "rgb(215, 226, 239)",
      "popup": "rgb(24, 26, 27)",
      "popup_text": "rgb(215, 226, 239)",
      "ntp_background": "rgb(32, 35, 37)",
      "ntp_text": "rgb(215, 226, 239)",
      "tab_loading": "rgb(215, 226, 239)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ebe2129f-c42b-43e5-a259-7e8033a331e9}"
    }
  }
}