Having set a comma as separator between player numbers, it seems this setting doesn’t get respected when changing the Engraving Options > Staff Labels > Numbering option “When stacking player numbers for condensed players vertically”:
See the F Horn staff labels on the left (next to the dialog)
(This is the state of the “Separator between player number” setting in Engraving Options > Condensing:
How could I get the comma displayed?