Sometimes 32GB are really not enough.
The RAM fills up more andd more until its full after an hour or so and the system start wild paging, game drop to 4-6 fps. With some luck you can quit to main menu but ram restores very very slow.
I am surprized to see that GPU-Z shows an RAM usage of up to 29GB while task manager only show up 8GB for msfs but there is not other ram consuming task.
Note that the VRAM is also maxed out.
Happens today over france to me. I have to have an eye on this bug.