Ah right, sorry: MacOS it was; but I guess Windows wasn´t updated either. Was talking about the downloadable, DRM-free version on Humble Store.
Another option would be to supply an itch.io key w/ purchases on DRM-free portals (don´t know if that´s possible on Humble though). That´s what some contributors on DRM-free bundles do. Nevermind: Just read your comment!