Hi, I´m trying to configure a multiline Text Box for an Attribute in my Feature Layer in ArcGIS Portal 10.9.1. In Map Viewer Classic, this works smoothly by choosing the desired TextBoxType (mehrzeilig=multiline)

But I have to use the new MapViewer to get the benefit of the CIM Symbol Support.
In the new Map Viewer, this option is no longer availabe.
In ArcGIS Online and later versions of AGE this function is available in the Layer Properties Section of the Webmap and the function "forms".

I revisited all documentation and the IssuesAdressed list for 10.9.1, but could not find a possibility to configure this function, nor a hint if this was deprecated in 10.9.1.
Any ideas how to set this up in the new map viewer?