…additional comment on this: as far as I can remember this STOPPED working a couple of years ago in MSFS2020.
It worked in the initial release of MSFS2020, but stopped working after an update at a couple of years ago.
We moved all of our mouse areas to the Behavior section - and they work fine.
Thanks for correcting me, and my most humble apologies for the inaccuracy - we moved away from the approach since it stopped working, and I am sure you are totally right.
But they definitely stopped working for us at a certain point, and we had to change all of our scripts.