http://bugs.winehq.org/show_bug.cgi?id=58887
--- Comment #14 from Nikolay Sivov bunglehead@gmail.com --- Thanks. It's right there:
--- 0124:trace:dwrite:dwritetextanalyzer_GetGlyphs L"U\200aN\200aL\200aO\200aC\200aK\200a \200aF\200aU\200aL\200aL\200a \200aV\200aE\200aR\200aS\200aI\200aO\200aN":37, ---
So text is originally interleaved with 0x200a "hair space" characters. This basically means we need to check if it should synthesize something if this character is missing from font, of if you'll get same null glyphs on Windows, when using a font without 0x200a support.