Examine source code of NaturSky

{
  "name": "NaturSky",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "84-841484_day-sky-wallpaper-4k.jpg"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(13, 63, 181, 0.27)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(255, 255, 255, 0.23)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 0.13)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4cdd5024-d8db-4d21-a7dc-e0193db98c71}"
    }
  }
}