Why do I get random page reloads only on iOS Safari 17.6–17.7?

I have an app at work that works fine up through iOS Safari 17.5 and from 18 it's also fine. On iOS (only iOS) Safari 17.6–17.7, the web app will reload the page for no apparent reason after five minutes or so.

Another strange this: when debugging the iPad's Safari through macOS, the connection to the iPad Safari seems to get cut off when this reload happens and I have to reopen the dev tools on the macOS version of Safari.