Starting from RS2, GDI on Windows gained Y-axis text antialiasing and is set to "on" for almost all Windows app (like Notepad). However Krita does not follow this pattern. Considering modern typography would introduced more and more please enable that for better text display. https://i.loli.net/2018/12/16/5c16478b1f07c.png (Related bugs for other products including Visual Studio are already filed.)
Um, we render the text using Qt, so this probably should be reported for the Qt toolkit. Unless Qt exposes that as a property, there isn't anything we can do.
Well some other applications like Snipaste is built using Qt too, but it has proper Y-axis AA and GASP table respect.
Also Qt supports DWRITE, so you can try that?
Where did you find that in the Qt documentation?
I am... setting this as wishlist.
I believe Qt _is_ using DirectWrite on Windows by default and we haven't done anything to change it. (The only other option is FreeType and trust me, it looks awful on Windows.) I can't tell if Qt has enabled vertical anti-aliasing for the menus. From your screenshot it looks like maybe it doesn't but it's a bit hard to tell for sure. The best way would be to check the source code of Qt. It's a very minor issue for Krita though, so it'd be low priority. And it'll still need to be reported on Qt's bug tracker.