Examine source code of Joker

{
  "name": "Jocker",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "6_2_2021 8_12_14 PM (4).jpg"
    },
    "colors": {
      "frame": "rgba(28, 28, 28, 1)",
      "tab_background_text": "rgba(207, 207, 207, 0.56)",
      "toolbar": "rgba(255, 247, 247, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(0, 0, 0, 0.32)",
      "toolbar_field_text": "rgba(255, 255, 255, 0.45)",
      "tab_line": "rgba(255, 255, 255, 0.32)"
    }
  }
}