FindSystemTimeZoneById doesn't return new object

The TimeZoneInfo object returned by FindSystemTimeZoneById(String) is now a cached TimeZoneInfo instance instead of a new object.

Previous behavior

TimeZoneInfo.FindSystemTimeZoneById(String) returned a new TimeZoneInfo object.

New behavior

Starting in .NET 8, TimeZoneInfo.FindSystemTimeZoneById(String) returns a cached TimeZoneInfo instance.

Version introduced

.NET 8

Type of breaking change

This change is a behavioral change.

Reason for change

This change was made to improve performance when calling FindSystemTimeZoneById(String). For more information, see dotnet/runtime pull request #85615.

Recommended action

If your code relied on FindSystemTimeZoneById(String) to create a new instance of TimeZoneInfo, refactor the code to call one of these methods instead.

Affected APIs

• System.TimeZoneInfo.FindSystemTimeZoneById(String)