Classic WoW: Unable to use Ranks in spell macros

I’ve tried just about everything I can think of. I’ve manually typed them in, tried dragging them over, copying macros that already use ranked spells, but I just can’t seem to get Spell Ranks to work.

If I type:
/castsequence [nogroup] reset=300 Rockbiter Weapon (Rank 1), Windfury Weapon (Rank 4)

This is what is saved:
/castsequence [nogroup] reset=300 Rockbiter Weapon, Windfury Weapon

Any ideas on what I’m doing wrong? Proper GSE versions, and have used GSE for years in retail.