Swashbuckling stance bonus not showing up in inventory details?

[Bingobong]

I created my first bard and tried out the new swashbuckling stance. I was using a rapier and expected the crit multiplier to go from x2 to x3. But it stayed at x2 according to the inventory details panel. I was not wearing any armor and didn't use a shield. Is this a bug or is there something I'm missing? I toggled the stance on and off and the crit multiplier remained the same (x2).

[Scrabbler]

Displayed crit mults fail to update in all kinds of circumstances.

Look at the weapon item window specifically, while it is equipped.