This domain is an example domain for demonstrating Signed Exchange Web Packaging.
If https://signed-exchange-testing.dev/sxgs/valid.html is loaded from a normally configured web browser, the returned document will simply be a normally served HTML document. However, if https://signed-exchange-testing.dev/sxgs/valid.html is requested by a useragent that sends the headers:
Then the document will be returned within a Signed Exchange with HTML payload.
For example, using the following commands:
curl -H 'Accept: application/signed-exchange;v=b3' https://signed-exchange-testing.dev/sxgs/valid.html -o valid.html.sxg
downloads a valid Signed Exchange file with an HTML payload.
$ go get -u github.com/WICG/webpackage/go/signedexchange/cmd/dump-signedexchange
$ ~/go/bin/dump-signedexchange -verify -i valid.html.sxg
verifies that the Signed Exchange file is valid.
More information about Signed Exchange can be found at the following links:
Various examples of valid and non-valid signed exchange documents: