Examine source code of MIKU CITY

{
  "name": "MIKU CITY",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "anime-girl-alone-fantasy-5k-3440x1440-3.jpg"
    },
    "colors": {
      "frame": "rgba(3, 3, 3, 0)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(3, 3, 3, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(179, 65, 65, 0)",
      "toolbar_field_text": "rgba(0, 0, 0, 1)",
      "tab_line": "rgba(112, 65, 65, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e1447810-15aa-4c38-9837-103bff8b12a2}"
    }
  }
}