The problem also exists with servers. As soon as something is finished in the furnace and it is not retrieved, the content is gone as soon as you leave the server. If you leave the server before the process (there must be nothing in the output) is complete and the chunk is no longer loaded, the items are still inside.
The fire animation also remains. Even if there is nothing left in the furnace.
TheRealFlatze
I can also confirm this.
The problem also exists with servers.
As soon as something is finished in the furnace and it is not retrieved, the content is gone as soon as you leave the server.
If you leave the server before the process (there must be nothing in the output) is complete and the chunk is no longer loaded, the items are still inside.
The fire animation also remains. Even if there is nothing left in the furnace.