Examine source code of BluerSky

{
  "name": "BlueSky",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "download (4).png"
    },
    "colors": {
      "frame": "rgba(0, 0, 0, 1)",
      "tab_background_text": "rgba(0, 102, 227, 1)",
      "toolbar": "rgba(23, 23, 23, 1)",
      "bookmark_text": "rgba(0, 102, 227, 1)",
      "toolbar_field": "rgba(23, 23, 23, 1)",
      "toolbar_field_text": "rgba(0, 102, 227, 1)",
      "tab_line": "rgba(0, 96, 230, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a872e595-4c1a-4c0d-8b9f-3f4413888dac}"
    }
  }
}