Can't "run all below" - "command is part of a batch that is still running"

[dkxxx-rc]

Weirdness in Databricks on AWS.  In a notebook that is doing absolutely nothing, I click the "Run All Above" or "Run All Below" button on a cell, and it won't do anything at all except pop up a little message near the general "Run All" button, saying "Command is part of a batch that is still running.  Please wait or interrupt current execution."  The pop-up disappears in about a second.

There is nothing to interrupt.  Furthermore, if I click "Run All", it starts running everything, no problem.

What's happening?

(See message in screenshot.)

[Advika]

Hello @dkxxx-rc!

Can you check if any background processes are still running in your notebook that might be interfering with new executions?
If you are using Databricks Runtime 14.0 or above, cells run in batches, so any error halts execution, and individual cells can't be cancelled, you'd need to interrupt and restart the entire batch.

[dkxxx-rc]

I had restarted the notebook and the cluster, so I'm doubtful about it having been hidden background processes.  The problem has not recurred in the days since I posted this topic, for what it's worth.