Good news! System.Drawing for .NET Core has been released as part of the Compatibility Pack for .NET Core.
You can use System.Drawing.Common. Issues related to System.Drawing.Common can be filed at http://github.com/dotnet/corefx/.
On Windows, there are no dependencies for System.Drawing.Common. On Linux and macOS, you need to install libgdiplus.
You can either install libgdiplus using your package manager. For example, on macOS, run brew install mono-libgdiplus.
On Linux, your distro probably includes a version of libgdiplus. That may be a very old version, though. Mono helpfully
packages libgdiplus for various distros, so you also use the Mono packages for libgdiplus. They contain more recent versions of libgdiplus.
Alternatively, you can use NuGet packages to install libgdiplus side-by-side with your application.
If use System.Drawing for .NET Core on OS X or Linux, make sure you reference the native packages: