Scrolling gets stuck on iOS Safari about tilt.build

[lizzthabet]

@Chimney42 and I were able to reproduce on an iPhone running iOS 14 and through XCode Simulator.

To reproduce:

1. Go to tilt.dev in Safari.
2. Try to scroll the page immediately. The page will not scroll and seem stuck.
3. After waiting several seconds, try scrolling again. The page should scroll just fine. (Lian reported that it took longer for scrolling to start working if she tried to scroll a lot when the page first loaded. I did not see a difference on my end through XCode Simulator.)
4. Disable Javascript for Safari under Settings.
5. Go to tilt.dev again in Safari, either by refreshing the page or opening a new tab.
6. Try to scroll the page immediately. The page should scroll just fine.'

Pinch zooming in and out didn't make a difference in our testing. (It seems likely that after pinch zooming, enough time had passed that the page was scrollable.)

[lianmakesthings]

I upgraded my phone to iOS (and Safari) 15, and the issue still persists