Hi. Does Forge not support the extra items that were added as fuel for furnaces in the 1.11 update? Bows, doors, carpets, etc? http://minecraft.gamepedia.com/1.11#Gameplay_2
It seems to be both on the client and server side... With a forge server and client (version 2199) you can't put the new items in the furnace at all, but if I connect a vanilla client to a forge server, you can put the items in, but the furnace doesn't start, and the items pop out when you close the interface (and it may also crash - crash log at http://pastebin.com/vJCgxBEp). If I connect a forge client to a vanilla server, then all but one of the items will be put in the furnace (or none if it's a bow) and the furnace will start working. The remaining item in your inventory will eventually disappear though.