Building a rogue, and the description tells me Key Ability should only be Dex, unless a Racket gives another option. I chose the thief racket, which should not provide any extra options, but when I go to select my Class Boost, which is also used to define the ability used for Class DC, I have the options of Strength, Dexterity, Intelligence, Wisdom, and Charisma.
Is this a bug/missing feature in Pathbuilder, or am I misunderstanding what it’s doing?
Yes exactly. It’s a superset of all of them