Examine source code of Microsoft Word Dark Mode

{
  "name": "Microsoft Word Dark Mode",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "trnsprtnpng.png"
    },
    "colors": {
      "frame": "rgba(38, 38, 38, 1)",
      "tab_background_text": "rgba(90, 139, 237, 1)",
      "toolbar": "rgba(56, 55, 55, 1)",
      "bookmark_text": "rgba(140, 140, 140, 1)",
      "toolbar_field": "rgba(38, 38, 38, 1)",
      "toolbar_field_text": "rgba(140, 140, 140, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4b7acc3e-48ce-49d8-a82a-598815e6d7df}"
    }
  }
}