http://directory.fsf.org/project/Windows32API/
    http://directory.fsf.org/project/wxwindows/
    http://wxwindows.org/about/credits.htm

    see the acknowledgment from one of the softwares endorsed by FSF your
    favourite organization.

    ==========================================================================================================
    Thank you to Microsoft for donating a copy of Visual C++ 6.0 to help
    wxWidgets compile on this version of the compiler (for a Virginia Tech
    course).

We do not refuse to list a program merely because it mentions
a non-free platforms on which it runs.  I've explained that already.

I don't like the warm and positive attitude towards Microsoft
expressed by that thank-you.  If wxwindows were a GNU package I would
ask the developers to change that.

But wxwindows is not a GNU package, and I doubt I have veryx much
credit with its developers.  I'd rather not use it on this.