When doing data assignments, its often hidden the content of name, data type and source. It becomes very hard to identify issues and visualize the data without knowing its full content. For instance, the full class name, or a constant expression.
As a suggestion, a couple of things could be done to improve the experience here, for instance adding some sort of tooltip that when the user hovers over the inputs, the full content is visible. Another potential enhancement could be to use the screen space more efficiently to expand the popup width size.
Allowing users to copy the content of these fields would be yet another great usability improvement IMHO.