@NickAtNight this is an iOS limitation. If you test, you’ll see that it doesn’t work on Safari, Firefox, Vivaldi, Chrome, or any web browser within iOS. I have reported this to Apple before but they claimed not to be able to replicate it. It didn’t matter what changes I made to any settings, what I reset, or anything else.
You should be able to check and realize the same, that it happens on all web browsers on iPhone (iOS).