When Windows Forms first appeared with the initial release of the .NET Framework in early 2002, Windows XP was still brand new and high DPI displays were several years away from being the norm in the PC market. For this reason, Windows Forms applications can look fuzzy when run on high DPI displays, and this is something we’ve seen with our Notepad control.

Fortunately, Microsoft added support for high DPI displays to Windows Forms via updates to the .NET Framework, and it has improved that support over the years as Windows 8 and then Windows 10 arrived. And as of .NET Framework 4.7, high DPI support in Windows Forms is pretty much complete and supports the latest OS features related to this functionality.