I just discovered a bug with the mobile menu when using IDs (smooth scrolling). After opening the menu and tapping on a menu entry, it doesn’t disappear automatically. Would be great if someone fixes that bug ASAP.
Sounds like the user is creating a single landing-page experience and nav menu may rely on a page turn. One solution may be to dismiss the nav menu if a link is activated and that link is a link to a page anchor (i.e. href starts with a # character).