I had an issue with my fences being split between two monitors. So not just on the wrong monitor, but 3 on one monitor, and 3 on the other. I rebooted, hoping that would clear it up. Instead, all the fences were half-sized (single column vs 3 column) and spread randomly across my monitor (rather than being laid out at the top.)
Any idea what is up with it? These "which window" issues are relatively new--I've had occasional cases over the last few years of the fences ending up on the wrong monitor, but since it's all the right sizing and location information otherwise, and see that there are whole forum discussions on that. And frankly, while a nuisance, that doesn't really bother me. This new bug is both new and really annoying.
Note: Windows 10, 2x1440 monitors. Fences 184.108.40.206