[Bug 44120] Steam Big Picture mode fails to display content, it shows a black screen (d3d10)

https://bugs.winehq.org/show_bug.cgi?id=44120

--- Comment #5 from Aaron Franke  ---
Considering that page hasn't been updated in 5 years, because Valve, the
requirements for Big Picture could have expanded to include DX11. The fact that
I see d3d11 stuff in the log hints at this.

But, fixing the DX10 issues does sound like the way to go. I can't tell which
of these stubs is an important issue, the d3d11 "not implemented" ones were
easy for me to spot because they said "not implemented" but I can't tell which
of the d3d10 stubs and fixmes are mostly informational and which are big
issues. So I'll leave that to Józef.