2sxc uses the Imazen ImageResizer for dynamic images. 

To also support WebP (new in 2sxc 11) we need to include the ImazenWebP extension AND a special DLL. Here's what needs to be done to get the latest DLL:

1. You need Visual Studio 2019 and you need to install the C Build Tools as well.
   1. To verify it works, open a special Developer Command Prompt (look for that in Windows) and then type nmake - just to see if it finds the command. If it doesn't you don't have all the prerequisites yet. 
2. Then you should download the latest libwebp from github [TODO]
   1. and unpack it
3. To compile it
   1. Open a Developer Command Prompt VS 2019 (or later) and change to the main directory of the downloaded package. 
   2. Now run this
      nmake /f Makefile.vc CFG=release-dynamic RTLIBCFG=dynamic OBJDIR=output
      Note that in the main readme a different command is listed, but that doesn't create a DLL
4. Now copy that generated DLL to wherever you need it

PS: Most of this data was collected from sources like

• https://github.com/imazen/libwebp-net/blob/master/libwebp-build-instructions.txt