Actually, it’s just the general debian stretch updates, nothing font related as far as I can see. The only specialty are the Liquorix kernel updates (served by Steve Pusser) approx. twice a week - that’s why I mentioned them.
Could Blizzard have changed the font? It seems that people agree it started with a battle.net update around Sep 12th.
Somebody suggested on Reddit
I’ve fixed it with “winetricks settings fontsmooth=rgb”
(a.k.a. ClearType in Windows)
@Dox can you say how to test this solution using lutris?