Examine source code of RS-Virtual

{
  "name": "RS-Virtual",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Firefox2.png"
    },
    "colors": {
      "frame": "rgba(242, 245, 250, 0.09)",
      "tab_background_text": "rgba(145, 203, 250, 1)",
      "toolbar_field": "rgba(0, 0, 0, 0.08)",
      "toolbar_field_text": "rgba(141, 179, 214, 1)"
    }
  }
}