Examine source code of Sombra Online

{
  "name": "Sombra Online",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "OSiOm01.png"
    },
    "colors": {
      "frame": "rgba(96, 11, 145, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)",
      "toolbar": "rgba(9, 0, 255, 0.12)",
      "tab_line": "rgba(230, 71, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c27393df-a9ec-4841-8d60-14c6885e0519}"
    }
  }
}