Intermittent HTML select freezes on Safari in iOS 15 onwards

Question

We have a single page app written in HTML/Javascript and our customers are experiencing intermittent freezes when using HTML select drop downs on Safari on iPads in all versions of iOS 15, but not on iOS 14 or earlier. Freezes often seem to occur when coming out of sleep mode. Closing Safari and reopening fixes the problem, but its still an inconvenience if input hasn't been saved etc. We have some legacy jQuery Mobile drop downs, but the problem occurs both with those and with plain JS ones.

We've tried restarting machines, checking storage, turning off any Safari extensions, turning off GPU Process Canvas Rendering (which seems to be on by default in iOS 15) and more. It doesn't seem to be specific to particular models as users have a wide range of these.

I know the UI of select elements was changed in iOS 15 - has anyone elese experienced problems with this?

Answer 1

Yes, I've experienced an issue with HTML selects that might be related to yours:

• create a desktop shortcut to a PWA with a HTML select
• open PWA
• click on select => should open (OK)
• press home button
• activate PWA again
• click on select => does NOT open

Restarting the app fixes the problem until the next reboot.

Checked that on iOS 15.1 to 15.4, error occurs on all systems. Works on iOS 14. I haven't yet found a reported issue.