Instance variables in descendants – PB Docs 2017

If you create a window by inheriting it from an existing window
that has public or protected instance variables with simple datatypes,
the instance variables display and can be modified in the descendant
window’s Properties view. You see them at the bottom of the General
tab page. In this illustration, the last property is an inherited
instance variable.

All public instance variables with simple datatypes such as
integer, boolean, character, date, string, and so on display. Instance
variables with the any or blob data type or instance variables that
are objects or arrays do not display.