[donatj]

As author of a popular User Agent parser - they are indeed a train wreck but they were at least a largely solved, managed and contained train wreck. The average person could just grab a library, pass it a single string and know what browser someone was using.

UA hints, SEC headers and all that stuff they’re pushing to “replace” it really just complicate the problem. Getting accurate data server side has been made a total pita.

[kijin]

Yeah, the problem with "just use feature detection" is that most of it only works on the frontend, or by having the frontend send additional data to the server after the initial page load.

Sometimes you need to optimize things for certain browsers or bots before a single byte of JS has been sent, relying only on the first few request headers. Akamai probably needs to.

Deleting the cruft but retaining the highest bits (product name and major version) like Chrome is doing seems like a reasonable compromise.