I have modified the Slideout Menu to appear full screen. And for closing the Slideout Menu, I have a added a button with class .slideout-close (I don’t remember exactly and I’m not mobile right now. linked site below).
It works fine on chrome but not on Safari web browser in Apple devices.
just tested this on iOS Safari physical and simulated devices and i am not seeing this issue. Which device is it ? Latest OS?
Worth checking for browser cache and any extensions that may be conflicting.