https://bugs.winehq.org/show_bug.cgi?id=55446
--- Comment #2 from Dmitry Timoshkov dmitry@baikal.ru --- (In reply to Alexandre Julliard from comment #1)
(In reply to Dmitry Timoshkov from comment #0)
Under Windows SendMessageW(LB_FINDSTRING) works just fine regardless of system locale.
Of course that depends how we define "works just fine" ;-)
It means that LB_FINDSTRING returns index of the correct listbox item.
I agree we don't want to use the C locale, but should it use the user locale instead? Or the thread locale? Or the default Unicode mapping table? Some tests would be interesting.
I'd guess that listbox is supposed to use the locale set by LB_SETLOCALE like it already does in other places of the code, that way it used to work before the problematic commit.