Versions

Betweenlands version:

3.6.0

Forge version:

1.12.2-14.23.5.2847

Singleplayer or Multiplayer:

Singleplayer

Installed mods:

Betweenlands
Phosphor
Optifine

Description of the problem

How to reproduce:

1. Take a mineral or anything that can be smelted in a furnace and grab some sulfur too.
2. Put everything in and remove the sulfur after it starts to melt.
3. Interact a few times with the furnaces.

This bug sometimes will appear and sometimes it's a bit weird on how it is triggered, hope the picture can help to see what is happening.

Expected result:

You should have a light source even when sulfur isn't in the furnace because something is still melting.

Actual result:

Instead, the light will sometimes disappear no matter how much time there is for the fuel to run out.

Pictures:

this is an Optifine bug, I don't use Optifine and it doesn't happen to me

Happens to me too, no optifine installed https://streamable.com/zqfi7o