Restarting leader zookeeper instance made quorum lost

[Bae, Jae Hyeon]

Hi zookeeper users

While rolling restart zookeeper cluster of 5 instances with 3 as quorum,
restarting the leader instance made quorum lost. Is this expected?
Otherwise, how can I restart the leader instance without interrupting whole
cluster? Or is this fixed in 3.4.6?

Thank you
Best, Jae