Update here: The bug is not resolved for even the latest NVIDIA drivers although it does appear to be reduced.
In the end I had to disable multi window and just drag the Flight Simulator window across both monitors which isn’t ideal (stretched and toolbar at top) but no flickering so its flyable.
Annoyingly Martial isn’t even aware of any issues, he said in the last developer stream the feature works perfectly. So I guess it means that this will also be broken in 2024? 
Mods can you please raise/move this to bugs?
Title: Multi Window mode has issues when Frame Generation enabled
- Texture juddering when Frame Generation is enabled with a 2nd window
- Frame Generation appears to only work on main window (limited by NVidia), resulting in half the FPS on the 2nd monitor which is very distracting.
- Often an additional window config will appear in Experimental Settings (a clone), so adding 1 window results in 2 configs showing
