Forge version: 1.15.2-forge-31-1-63
Botania version: Botania-r1.15-383.jar

Steps to reproduce:

1. First step: craft runic alter
2. Second step: place runic alter
3. Third step: fuel side of the furnace should not accept coal

What I expected to happen: to make iron ingots
What happened instead: nothing :/

This issue is stale because it has been open for a while with no activity. Remove stale label or comment or this will be closed soon.

...what?

I have no idea how your steps and your expectation are tied together in any way