New in Microsoft Edge Version 82.0.421.0 (Official build) canary (64-bit)
Reason for doing it is more about privacy and stopping fingerprinting.
Freeze User-Agent request header
Set the User-Agent request header to a static string that conforms to the current User-Agent string format but only reveals desktop vs Android and if the 'mobile' flag is set – Mac, Windows
to be more effective, also enable this flag:
Reduce default 'referer' header granularity
If a page hasn't set an explicit referrer policy, setting this flag will reduce the amount of information in the 'referer' header for cross-origin requests. – Mac, Windows