Over here we call them CRAFT moments.
If you're looking for the FPS display controls in Steam then go to:
Steam -> Settings -> In-Game
and you'll find the In-game FPS counter setting with:
- Position pull-down option; and
- High contrast color tick-box (which does what is says despite the spelling!).
If its the War Thunder HUD FPS display you're wanting to change...
...the little Googling I did seemed to indicate there is no user control for it.
Happy to be corrected by anyone who knows differently :)