If I set the template of listbox LabelTerm I got the right UI but the terms (which are custom format) are shown overstroken. If I put the template type to "Label", the ui gets compiled very differently, the supplier looses its name and does not fit in the CollapseBox any more. Any hint?
It's great to see you digging around in the UI. Let me start this conversation with saying that the ListBox control is a complicated beast which is still getting fine tuned. Because of the complexities of the ListBox definition the compiler can very quickly have difficulty applying generic layout patterns (although it can still be improved). But independent of that, let first start with, what is your custom format?
A TermLabel has by default it's format set to `term`. This can be overridden. The danger of overriding the format of a specific control is making sure that our custom format has all the functions of the original format so that the control won't get into trouble. As you already know js doesn't have very strict typing. By the looks of it the format that you created in rtermFormat.js has the same functions as the term format so there should be any problems. So if you add `format: './rtermFormat'` as shown below, to the u.yaml file, it should work in regards to the format layout. Fingers crossed.