Evokers have a unique "charging" or "empowering" type of spell where the longer we hold it the more powerful it becomes. This is typically shown on our cast bar with tick marks as it charges up.

All other spells are still showing on the cast bar, but the Fire Breath and Eternity Surge (empowered spells) are no longer showing, which makes it difficult to tell how many tick marks/charges we're building.

I've played with disabling various types in the setting (swing timer, spells, etc), but nothing makes the empower bar reappear.