Frame generation, MSFS, and focus in Windows?

[Will]

MSFS supports frame generation, which is the addition of an interpolated "frame" between every GPU-rendered frame, which doubles your effective frame rate, or more practically, lets you render fewer frames for the same optical result while using more GPU overhead for other things. Think: all settings on Ultra.

I assumed this wasn't available for those of us with Nvidia 30xx cards, until last night when I found a mod online that enables frame generation in MSFS for any RTX card. Wow, it's beautiful, even on my lowly 3060.

Sadly, MSFS turns frame generation OFF whenever MSFS loses the focus in Windows. Given that I run MSFS and PSX on the same computer, and the focus is on PSX and almost never on MSFS, that means I can almost never really appreciate frame generation in practice.

I don't suppose there's a workaround for this? Some way to trick MSFS into thinking it has the focus? Some way for the OS to give focus to more than one window at the same time?