My bed and breakfast website has a menu button which opens a page on the travel venue, TripAdvisor, so that potential guests can read reviews of the property from previous visitors. The button, labeled "Reviews", works correctly on a desktop, notebook or iPad, but not on an iPhone. On an iPhone, the menu button opens a page which just shows a TripAdvisor logo, with unending animation, and the review page never loads. I'd like to know what causes that, and how to fix it. My website is at www.mauitradewinds.com
2) Fix all WebPageTest Security Issues as site has HSTS disabled which might be related.
3) Reviews tab works fine under various mobile emulators, so likely, as @Kimputer suggested, this is likely an issue related to the specific iPhone being used.
4) Random item to test, be sure to also turn off all Ad Blockers running on the iPhone too.
5) Also try temporarily disabling the https://nht-2.extreme-dm.com callout on the site, as this is the only external site callout (beside to Google) which might also be causing a problem... still... related to the specific iPhone or iOS version being used...