Hi all, I have installed yaboot with macOS, OSX and debian onto a powerbook. It worked very well. Then when I tried to change starup disk in OSX, then the yaboot menu doesn't show up at booting; the machine immediately boots up to OSX. Booting to debian (using OF and the magic string boot hd:2,yaboot) and rerun ybin didn't help. How can I fix this problem? Thanks, Thanh