I first noticed this in older version and then tried v1.18.1 in a test instance. Chrome (Windows 10) and Safari (iPadOS) exhibit the issue. However with Firefox (Windows 10), I can create a ticket.
I added *.domain.com to allow System iFrame in settings. Without this, I don’t even see the welcome to the support center page as expected.
Creating tickets without iFrame works ok with the problem browsers.
I was hoping that this seemingly browser specific issue was because my production instance of OSTA was old.
I made minimal changes to OSTA – just the System iFrame thing.
Any ideas on how to troubleshoot this issue further?