Summary: After I saved/loaded to attempt a workaround for another issue, the fire in my firepit was missing. The log was still there (so it’s not quite like this otherwise apparently similar old report), as was the actual lighting effect and the sound effect of the crackling fire; just the visual effect of the fire itself was missing. See attachment.
Steps to reproduce: Not sure if consistent, but I guess just save/load when the campfire is lit.
Fire is lit at 14:11 (you can tell from the flash), immediately before save/load. After loading (±14:30), the fire is apparently lit again (another flash and sound effect), and then at 14:53 you can see the invisible fire (uh…).
Versions and mods: No mods, latest release version in Steam at the time of writing, version 0.1.0 (release 166) according to the title screen.
OS: Windows 8 Pro 64 bits (6.2, build 9200)
Processor: Intel® Core™ i5-3450 CPU @ 3.10GHz (4 CPUs), ~3.5GHz
Memory: 8192MB RAM
DirectX-version: DirectX 11
Graphics card: NVIDIA GeForce GTX 660