Examine source code of after

{
  "name": "after",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "Untitled.png"
    },
    "colors": {
      "toolbar": "rgba(151, 5, 153, 1)",
      "toolbar_field": "rgba(23, 22, 22, 1)",
      "toolbar_field_text": "rgba(0, 0, 0, 1)",
      "frame": "rgba(124, 15, 219, 1)",
      "tab_background_text": "rgba(148, 53, 230, 0)",
      "bookmark_text": "rgba(20, 1, 1, 1)"
    }
  }
}