chromium/components/background_fetch/README.md

# Background Fetch

This component contains code which implements [BackgroundFetchDelegate](content/public/browser/background_fetch_delegate.h)
using a [DownloadService](components/download/public/background_service/download_service.h). The UI is implemented by
embedders by way of embedder-specific specializations of `BackgroundFetchDelegateBase`.

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See also:
- [Introducing Background Fetch](https://developers.google.com/web/updates/2018/12/background-fetch) for a primer on the
  Web API.
- [Demo site](https://bgfetch-http203.glitch.me/) to see it in action.