Examine source code of CUBST1

{
  "name": "CUBST1",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "cubist-1b.png"
    },
    "colors": {
      "frame": "rgba(134, 23, 232, 1)",
      "tab_background_text": "rgba(245, 10, 233, 1)",
      "toolbar": "rgba(169, 48, 199, 0.31)",
      "bookmark_text": "rgba(245, 10, 233, 1)",
      "toolbar_field": "rgba(30, 54, 235, 0.64)",
      "toolbar_field_text": "rgba(245, 10, 233, 1)"
    }
  }
}