Why does 2021a not remember new current folder?

In all the versions of Matlab prior to 2021a, the system would change the current folder to match the script under debug. Now it changes the folder, but does not remember it on the next debug run and I have to confirm "Change Folder" on every debug run. This happens even when the "Current Folder" view shows the script I am debugging. I've been reverting to 2020b to avoid this. Is there a preferences setting that I've missed?

pwd shows my default folder which agrees with the current folder window

dir(filename) does a directory on the script I'm trying to debug.

[Walter Roberson]

This can happen if you do not have write access to your preferences directory, which you can find the name of with prefsdir()