Examine source code of 2021 Edition

{
  "name": "2021 Edition",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Firefox 2021.png"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 1)",
      "tab_background_text": "rgba(255, 72, 0, 1)",
      "toolbar": "rgba(148, 56, 148, 1)",
      "bookmark_text": "rgba(255, 51, 0, 1)",
      "toolbar_field": "rgba(255, 104, 3, 1)",
      "toolbar_field_text": "rgba(225, 0, 255, 1)"
    }
  }
}