Fix mobile menu collapsing on scroll in iOS Safari#2261
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PeterKnightDigital wants to merge 1 commit into
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Fix mobile menu collapsing on scroll in iOS Safari#2261PeterKnightDigital wants to merge 1 commit into
PeterKnightDigital wants to merge 1 commit into
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iOS Safari fires a resize event when scrolling because the browser
address bar hide/show changes window.innerHeight. The initResizeHandler
was unconditionally hiding the nav on every mobile resize, collapsing
a menu the user had intentionally opened.
Guard the classList.add('hidden') call so it only runs when the menu
is not currently expanded (aria-expanded !== 'true').
Co-authored-by: Cursor <cursoragent@cursor.com>
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What this fixes
On iPhone and iPad, opening the mobile navigation menu and then scrolling down causes the menu to snap closed before you can tap a link. This makes it impossible to navigate the site using the mobile menu on iOS Safari — a potentially significant issue given how much traffic comes from mobile devices.
Why it happens
iOS Safari fires a
resizeevent whenever the user scrolls, because the browser address bar slides away as you scroll down (changing the visible height of the page). The menu's resize handler interpreted this as a layout change and hid the navigation menu — even if the user had just opened it intentionally.The fix
A one-line guard checks whether the menu is currently open before hiding it. If the user has the menu open, the resize event from scrolling is ignored. The menu still closes correctly in all other cases (e.g. rotating the device, resizing a browser window on desktop).
Steps to reproduce (before fix)
Test plan