When you open the pie chart for FPS/TPS by pressing shift + F3 it becomes watermarked, almost, never leaving the screen. Normally after pressing F3 to close the screen, the pie chart disappears however in this version, it stays on the screen no matter what, even on the main menu. To reproduce, simply go into a new world on snapshot 20w06a and press shift the, while holding down shift, press the F3 button.
Also, when you open F3 mode again, the pie chat and the FPS/TPS charts will become "hidden" again. This glitch does not effect the TPS/FPS chart.