https://bugs.winehq.org/show_bug.cgi?id=40450
--- Comment #8 from Fincer fincer89@hotmail.com --- Well, so that's the crash event occuring every time I launch my 64-bit Windows Steam client. (unspecified program crashes, haven't looked further into it). It hardly affects Steam client behavior in general.
Generally, I've tried to keep my wineprefix/debugging environment as clean as possible (no DLL overrides) so far.