An HTTP header caused time.gov to skew from UTC

4 hours ago

NIST's time.gov website provided inaccurate clock offset estimates due to an HTTP header causing extra network round trips.
The issue stemmed from the 'Connection: close' header, forcing new connections for each request and invalidating the NTP-like time adjustment.
The fix involved changing the header to 'keep-alive', reducing round trips and improving accuracy, but precision could still be enhanced with PerformanceResourceTiming.

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