MirrorMaker2 is not always starting tasks

I am using MirrorMaker 2.0 and running it via MirrorMaker.java
<https://github.com/apache/kafka/blob/2.7/connect/mirror/src/main/java/org/apache/kafka/connect/mirror/MirrorMaker.java>
class.
This method will start up it's own worker and`DistributedHerder`.

After upgrading from version `2.4.0` to `2.7.1` I noticed that when I am
starting up mirror maker it does not always start tasks - just the
connector is running. Doing some amount of stop/starts will eventually
start tasks too.

I summarised a problem and my investigations in this JIRA:
https://issues.apache.org/jira/browse/KAFKA-13196

Does any one face similar behavior? Or am I doing something inappropriate?

Thanks,
Jozef