https://bugs.winehq.org/show_bug.cgi?id=37615
--- Comment #1 from David Heidelberg (okias) david@ixit.cz --- So I investigated more and it's not so bad.
It's not directly related to FIXME code (which could be fixed, but it doesn't matter).
It start go trough list of fonts and on first place it hits Ahem font from Droid font suite. Trick is, this font is exactly (at least as I see in preview) made from white blocks.
So this brings me to idea, could there be some default preferred font?