Examine source code of Dark Horizon v2

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Dark Horizon v2",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-011-d53e0d0d1538ed554a90e056a2f04eca.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(255, 255, 255, 0.7)",
      "toolbar_text": "rgb(77, 77, 77)",
      "frame": "rgb(157, 157, 157)",
      "tab_background_text": "rgb(31, 31, 31)",
      "toolbar_field": "rgba(255, 255, 255, 0.75)",
      "toolbar_field_text": "rgb(73, 73, 73)",
      "tab_line": "rgb(186, 186, 186)",
      "popup": "rgb(240, 240, 240)",
      "popup_text": "rgb(40, 40, 40)",
      "tab_loading": "rgb(186, 186, 186)"
    }
  }
}