It´s still 100% OOTB available in Release 2023 [emoticon:44a8a53ad3364ea78a16c5a3229f75bb]. It works together with the "Class Path" property in "Properties". But it's really not a feature that is used a lot anymore. It survived in our environment since 11SP3 from 2015.
I will try to reproduce it next week, but this behavior is really quite random. Maybe it helps to simulate a "bad internet connection" with the browser debugger.
So it is! [emoticon:9d27520b879541edb4dc3688e695ae44] Thanks for the screenshot. I've looked at the ItemType form so many times, and I've always glossed over that field.
I'll need to install a 12SP7 version myself, but I can take a look and see if anything obvious jumps out to me as to why this tab wouldn't load.
