Examine source code of blank (black)

{
  "name": "blank (black)",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Untitled 2.png"
    },
    "colors": {
      "frame": "rgba(0, 0, 0, 1)",
      "tab_background_text": "rgba(41, 41, 41, 1)",
      "toolbar": "rgba(23, 23, 23, 0)",
      "bookmark_text": "rgba(46, 37, 37, 1)",
      "toolbar_field": "rgba(18, 16, 16, 1)",
      "toolbar_field_text": "rgba(0, 0, 0, 1)"
    }
  }
}