islandora_base_theme: Severe scrolling problem on mobile (iOS)

[alxp]

Was wanting to test the theme on my mobile device (iPhone 11, iOS 14.5.1). But I was unable to log in because when I scrolled the page, it would either pop back up to the top or the whole page contents would disappear.

I've attached a movie with this behaviour. I am not familiar with debugging such behaviour on-device so I don't have any educated guesses as to the cause.

RPReplay_Final1621435414.MP4

I consider this a pretty severe bug My colleague was not able to reproduce on his Android device.

[alxp]

Confirming that this is also a problem in the base bootstrap theme.

Propose that fixing this is over our heads and we probably should abandon this theme stack

[dannylamb]

Is there any @Islandora/8-x-committers who'd be willing to test / confirm this?

[kayakr]

FYI, I'm not seeing this issue at https://archivescentral.org.nz/user/login but we're on Bootstrap Barrio with Bootstrap 4.x