Examine source code of Vivaldi Red Dark

{
  "manifest_version": 2,
  "version": "2.1",
  "name": "Vivaldi Red Dark",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(65, 64, 59)",
      "bookmark_text": "rgb(228, 228, 220)",
      "frame": "rgb(65, 64, 59)",
      "tab_background_text": "rgb(228, 228, 220)",
      "toolbar_field": "rgb(43, 42, 38)",
      "toolbar_field_text": "rgb(228, 228, 220)",
      "tab_line": "rgb(205, 63, 55)",
      "popup": "rgb(65, 64, 59)",
      "popup_text": "rgb(228, 228, 220)",
      "tab_loading": "rgb(205, 63, 55)",
      "ntp_background": "rgb(65, 64, 59)"
    }
  }
}