Web kiosk can be brought out of full screen with a single swipe on a touchscreen

[TheGreenAirplane]

Hello,
I tried your web-kiosk on Debian 12 running on a kiosk PC with a touchscreen. I was able to figure out how to bring it out of full screen without a mouse or a keyboard in about 10 seconds. All it took was a downward swipe from the top edge of the screen. As kiosk machines frequently have touch screens, I was hoping this would behave robustly with one.
Is there a way to fix this? Some sort of setting maybe?