Great idea, @nok.
Unfortunately, it will not always work due to this bug in the notebook software:
So go to current running cell will take you to the first stuck cell instead forever.
I think more people need to chime in that bug report with words and not just +1s so that someone at jupyter dev will actually do something about it.
And I hope you also integrate the autoscroll with your extension too (except it has the same problem because of that bug).