This bug is basically Devices/Power source (item) that can be multiplied. To replicate:
- Collect Materials for your item.
- Prepare a worthless block/your old Device.
- Arrange your materials on the Assembler to create your item.
- Make your item and then make it replace your block/old Device.
- You will notice that the materials for your item is still intact.
All done! You can keep on making items until you do not have any more blocks/Devices. The bug was tested on Update 1.91. This bug may be fixed in a future update (unlikely).