Examine source code of Arctic Darkness

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Arctic Darkness",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-024-8de86d890779309c9a66423c64daa480.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(39, 39, 39)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(148, 172, 196)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(148, 172, 196)",
      "tab_line": "rgb(101, 160, 220)",
      "popup": "rgb(27, 40, 45)",
      "popup_text": "rgb(148, 172, 196)",
      "button_background_hover": "rgb(0, 0, 0)",
      "sidebar_border": "rgb(110, 149, 189)",
      "sidebar_highlight_text": "rgb(148, 172, 196)",
      "tab_loading": "rgb(101, 160, 220)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6667c629-85af-45b2-a660-482606f45200}"
    }
  }
}