Clustering method selection: immediate start

Hello!
When selecting one of the clustering methods, it immediately starts and there seems to be no way to block the process unless escaping the popup window.
This is frustrating when switching to time-consuming methods (eg Nearest Neighbor): the proposed default is with 6 blocks char but I already know I need a larger value. Nevertheless I have to wait for the default process to finish.
Is there any way to stop the default or to avoid auto-start?
Thank you!

Which version of OpenRefine are you using?

In 3.9 the default setting is to manually start clustering, but you can switch to the old behavior by activating "Auto-start" in the clustering window.