Start an Activity without Parent

UnparentActivity.cs

class A
{
  public void Foo()
  {
    // Hold onto current activity, clear current to prevent automatic parenting
    var current = Activity.Current;
    Activity.Current = null;
    try
    {
      using var activity = Telemetry.ActivitySource.StartActivity("bar");
    }
    finally
    {
      // put the previous activity back
      Activity.Current = current;
    }
  }
}