Hiding staff messes with instrument change

In setup, I have a player with a multistaff instrument (e.g. harp, piano, etc.) and a percussion kit instrument (i.e. two percussion lines). The part layout allows instrument changes. The first flow works as expected; nothing here. But in the second flow, at some point, I need to hide the bottom staff of the multistaff instrument, and later on show it back. If I do this, for some reason, the percussion instrument appears throughout the whole flow, even if it hasn’t a single note written. I can’t find a way to hide it.
Is this Dorico-related or am I making something wrong?

You cannot have both extra staves and instrument changes for the same player at the same time at present.