I've implemented nice feature making possible to use image spec as :mask property for the image. This allows making simple image/mask composition in Emacs.
I need this feature to implement avatars in circles for https://github.com/zevlg/telega.el/ project directly in Emacs without executing external programs.
I have done it only for X Window System, I have no experience with coding for Windows. Any help to implement it for Windows as well is very helpful