Examine source code of DarkMinimalSleek

{
  "name": "DarkMinimalSleek",
  "manifest_version": 2,
  "version": "4.0",
  "theme": {
    "images": {
      "theme_frame": "empty-png.png"
    },
    "colors": {
      "frame": "rgba(24, 24, 27, 1)",
      "tab_background_text": "rgba(70, 70, 73, 1)",
      "toolbar": "rgba(31, 31, 35, 1)",
      "bookmark_text": "rgba(70, 70, 73, 1)",
      "toolbar_field": "rgba(24, 24, 27, 1)",
      "toolbar_field_text": "rgba(70, 70, 73, 1)",
      "tab_line": "rgba(70, 70, 73, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a9b72a0d-a2b8-40ea-82cd-ff1f5768df96}"
    }
  }
}