https://bugs.winehq.org/show_bug.cgi?id=25703
--- Comment #15 from Vincent Povirk madewokherd@gmail.com --- Should be fixed by https://source.winehq.org/git/wine.git/commit/faa7564d375a6d4672da0bfe35f367...
Upstream winforms has also merged a fix (different from my work-around).