Chromium – the web browser stewarded by Google - have announced a plan to diminish the role of the HTTP User-Agent header in future versions of Chromium during 2020. While the engineering arguments for the change make some sense, the replacement solution – client hints – is far from proven, and details remain unclear. The proposal is yet to be agreed, and is just that, a proposal.
In summary, the User-Agent HTTP header will need to be used in combination with other secondary headers to retrieve device information. It is almost identical to the techniques already required to fully identify devices running browsers such as Opera or UC. As such 51Degrees data files and APIs already support the concepts of client hint user-agent header without any modifications to the deployed API.
These additional headers will not be available during the first web request and will only become available on the second. Having significant performance implications for some scenarios, which should be discussed more thoroughly before Chromium and Google progress with their proposal.
This blog provides a summary of the proposal, how to get involved, the implications, and the technical changes to consider for users of device detection.