Examine source code of Nature

{
  "name": "Nature",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "big ass moon.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(76, 126, 158, 1)",
      "bookmark_text": "rgba(49, 87, 140, 1)",
      "toolbar_field_text": "rgba(80, 63, 153, 1)",
      "tab_line": "rgba(105, 118, 201, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{5140c16a-458b-489e-be84-12525abc146d}"
    }
  }
}