Examine source code of Summers

{
  "name": "Summers",
  "manifest_version": 2,
  "version": "6.0",
  "theme": {
    "images": {
      "theme_frame": "SummersH.jpg"
    },
    "colors": {
      "frame": "rgba(3, 22, 163, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(17, 156, 237, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(17, 156, 237, 0.08)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 250, 250, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6f3555c5-24f0-4bc3-ba46-df8e7ba89cdb}"
    }
  }
}