Examine source code of Microsoft Edge Dark Mode

{
  "name": "Microsoft Edge Dark Mode",
  "manifest_version": 2,
  "version": "5.0",
  "theme": {
    "images": {
      "theme_frame": "backk.png"
    },
    "colors": {
      "frame": "rgba(32, 32, 32, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(59, 59, 59, 1)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(43, 43, 43, 1)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(19, 19, 19, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c180cbc3-59d5-4ab3-89f2-98e6efde7a0c}"
    }
  }
}