Mono's Winforms is a managed implementation written in C# that runs on Linux. System.Windows.Forms in Mono is implemented using System.Drawing What's missing from WinForms? Mono support for .NET 1.0/1.1 Winforms is 100% complete. (since Mono 1.2) (track progress) Mono is missing a few things from Winforms 2.0. (track progress) * WebBrowser - [1], [2]. The WebControl is being implemented using Gecko. However, Miguel de Icaza states that WebKit would have been a better choice.[3] Because of the work done on integrating Gecko, there are no plans to switch to WebKit.