Examine source code of Barn Owl by MaDonna

{
  "name": "Barn Owl by MaDonna",
  "manifest_version": 2,
  "version": "4.0",
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "rgba(41, 41, 41, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(43, 43, 43, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(43, 43, 43, 0.08)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 252, 252, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7135f9fc-458c-484b-989c-dee339c8bcf0}"
    }
  }
}