Does not copy Jera
What changes
The old Blank Card and Jera copying setup belongs to earlier versions. Holding Jera does not give Blank Card a Jera activation in Repentance.
How to approach the setup
Look for Clear Rune if the plan is repeated Jera effects. Blank Card remains a card-copying tool.
A practical suggestion for this pair. Check the rest of your inventory and the room before relying on it.
The caution to remember
Older videos can show a real interaction that does not apply to the installed version. Check the DLC before building around it.
What this teaches about a run
An incompatible pair is useful to recognize before spending resources on a setup.