WinForms wanted to be more like VCL. That's what it most closely resembled. Common controls, especially shell controls, come in different versions of comctl32

WinForms wanted to be more like VCL. That's what it most closely resembled. Common controls, especially shell controls, come in different versions of comctl32 etc. and have been versioned and dynamically selected in the basis of things like application manifests for backward compatibility reasons for a long time. https://docs.microsoft.com/en-us/windows/desktop/controls/common-control-versions https://docs.microsoft.com/en-us/windows/desktop/controls/co... API structures have different sizes so code usually needs to change to support later versions.