onEnter triggered in Chrome, but not on iOS (if window is scroll ancestor)

[derwaldgeist]

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I was able to implement react-waypoint successfully in combination with a div that had been set to overflow-y: scroll. I've set the bottom offset to 300 and am reacting to the onEnter event. This combination works just fine.

However, I then wanted to use the same approach on a scrolling page, without a scrollable div, i.e. just the regular browser window. react-waypoint picks up the window as its scroll ancestor, and everything seems to be setup correctly. It works fine under Chrome on macOS. If I try to scroll on an iOS device, however, nothing happens. If I enable debug mode, only the scroll ancestor and its dimensions are being printed out, but nothing happens if I start scrolling. It confuses me, because this scenario seems to be the simpler scenario to me.

What might go wrong here?