pf2e.fyi
From Pathfinder Secrets of Magic, which isn't enabled.

Wellspring Mage Dedication

FEAT 2
RAREARCHETYPECLASSDEDICATION
Prerequisites wellspring magic

There's no longer a limit on how many temporary spell slots you can gain per day from wellspring magic.

Special You can't select another dedication feat until you gain two other feats from the Wellspring Mage archetype.
Pathfinder Secrets of MagicOGL