https://bugs.winehq.org/show_bug.cgi?id=53770
--- Comment #23 from Nikolay Sivov bunglehead@gmail.com --- Locale issue should be fixed now with https://source.winehq.org/git/wine.git/commit/4172c0482626b56c76fd1e5e362a37....
Please rebuild with current wine, or wait for wine 7.20.
Arguably, it's also an application bug, if it really assumes it's safe to increment returned digit characters.