chromeos/components/media_app_ui/resources/manifest.json

{
  "name": "$i18nRaw{name}",
  "short_name": "$i18nRaw{name}",
  "start_url": "/",
  "display": "standalone",
  "theme_color": "#202124",
  "background_color": "#3c4043",
  "icons": [
    {
      "src": "system_assets/app_icon_256.png",
      "sizes": "256x256",
      "type": "image/png"
    }
  ],
  "file_handlers": [
    {
      "action": ".",
      "name": "Media File",
      "accept": {
        "image/*": [],
        "video/*": []
      }
    }
  ]
}