Many times I have a generic blueprint driving more specific blueprints. I discovered if you place a mesh, the mesh of the parent is your thumbnail and you can’t change it. So I add it dynamically instead. Then you have place it in the level and take a screenshot. I would rather have it take a screenshot in a “clean location” like the viewport of the blueprint editor.
Also the ability to get the proper screenshot from a specific blueprint without having to add the mesh dynamically would be nice as well.