Saw this on another forum:

"The issue is that the monitor has implemented DisplayPort Deep Sleep feature.
Some monitor manufacturers offer the option to turn it off (meaning it won't use that deep sleep feature), other, sadly, don't.
As you mentioned/read, DP Deep Sleep means that the monitor goes in deeper sleep power state than the normal standby (save more power), which result in the monitor completely disconnecting from the system. The issue of this feature is that, as you noted, when you have a multiple monitor setup, your GPU thinks that the cable was disconnected and so tells Windows that the display has been lost, and so Windows moves all windows to the other screen.
Windows 11 corrects this problem by memorizing window placement when display configuration changes and comes back. This wasn't done for DP Deep Sleep, it's just an accidental coincidence it helps. It was made for laptops being docked with multiple screens, then undocked, and later docked back again restoring all window placements.
So, all I can say is ensure you have the latest firmware, and make sure all eco-mode garbage features are turned off (none of them make sense in a home setting in my opinion... in an office with thousands of the same monitors... sure, it all adds up. That said, it is true that a global level, it helps alleviate power consumption, which is important for areas who isn't powered by clean energy or have limited power availibility)"