Failed to reconfigure connector's tasks after upgrading MirrorMaker 2 to 2.9

Issue

After upgrading MirrorMaker 2 (included in Streams for Apache Kafka) from 2.5 LTS to 2.9 LTS, it is possible to see this error in the log:

[yyyy-mm-dd HH:MM:ss,zzz] ERROR [Worker clientId=backup->active, groupId=backup-mm2] Failed to reconfigure connector's tasks (MirrorCheckpointConnector), retrying after backoff. (org.apache.kafka.connect.runtime.distributed.DistributedHerder:2195)
org.apache.kafka.connect.errors.RetriableException: Timeout while loading consumer groups.
    at org.apache.kafka.connect.mirror.MirrorCheckpointConnector.taskConfigs(MirrorCheckpointConnector.java:138)
    at org.apache.kafka.connect.runtime.Worker.connectorTaskConfigs(Worker.java:398)
    at org.apache.kafka.connect.runtime.distributed.DistributedHerder.reconfigureConnector(DistributedHerder.java:2243)
    at org.apache.kafka.connect.runtime.distributed.DistributedHerder.reconfigureConnectorTasksWithExponentialBackoffRetries(DistributedHerder.java:2183)
    at org.apache.kafka.connect.runtime.distributed.DistributedHerder.lambda$reconfigureConnectorTasksWithExponentialBackoffRetries$47(DistributedHerder.java:2199)
    at org.apache.kafka.connect.runtime.distributed.DistributedHerder.runRequest(DistributedHerder.java:2402)
    at org.apache.kafka.connect.runtime.distributed.DistributedHerder.tick(DistributedHerder.java:498)
    at org.apache.kafka.connect.runtime.distributed.DistributedHerder.run(DistributedHerder.java:383)
    at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
    at java.base/java.lang.Thread.run(Thread.java:833)