When block selecting with the scroll wheel on an active furnace, it gives you the block id of an active furnace. allowing you to place a dummy :light_bulb_on: furnace.
Who to reproduce...
1. burn something in a furnace in creative mode
2. use quick block selector on furnace.
3. place block (showing up as an active furnace)
Duplicate of MC-8112, please use the search function to see if your bug has already been submitted. Currently over 53% of tickets are being closed as duplicate.