http://bugs.winehq.org/show_bug.cgi?id=60172 --- Comment #6 from Wehrwolfmann <wehrwolfmann@gmail.com> --- I have a reproducer now that needs nothing but a prefix with dotnet48 in it. The attached bug60172.cs is twenty lines of code and builds with the csc that .NET Framework installs itself; the build line is in the file header. With no arguments it asks for Segoe UI and never reaches a window - it dies in MS.Internal.Shaping.TypefaceMap.MapUnresolvedCharacters through Environment.FailFast. Hand it any installed family without Cyrillic and you get the .notdef boxes from my first report instead. Both screenshots are attached. You were right that GDI fallback is not what WPF needs, but the replacement list does reach it. My prefix has none of the families GlobalUserInterface.CompositeFont names for U+0000-U+052F, so five entries under HKCU\Software\Wine\Fonts\Replacements cover it: Segoe UI, Segoe UI Symbol, Ebrima, Microsoft Sans Serif and Lucida Sans Unicode. As REG_MULTI_SZ they prefer Noto Sans and end at Tahoma, which Wine ships anyway. Patch for wine.inf attached. -- Do not reply to this email, post in Bugzilla using the above URL to reply. You are receiving this mail because: You are watching all bug changes.