While I waiting for some response (I had lunch and then) I decided to do something else on this notebook, so I cloned it...

I have some initialization code in the notebook. It was taking 60 sec before and after cloning 1.4 sec. Wow!

Did you (Databricks support) do something on the cluster?

I am going to run my etl command.

It was running very fast and then it got "stuck" again. I do not see any Spark job running.