GTK apps text not in font, maybe using wrong encoding

[jlittle]

(This really pre-release testing, as I did do-release-upgrade -d.)

GTK applications can't display any text, for example, this is xsane:

Qt apps are fine, and my clean install of Focal does not have this problem.

[jlittle]

It was the font. On eoan I used "Nimbus Roman No9 L" with no trouble, but on focal GTK apps don't like it. Shame, I like narrow roman fonts.

[altdel]

Fonts not rendering correctly

I upgraded my Kubuntu 19.10 to 20.04 and quite a few of my gtk applications can't show the fonts correctly. For example, gvim's menu bar fonts won't show correctly (it shows as rectangular boxes like the texts in above attachment). In Terminator and Synaptic, all the fonts are not rendering correctlly.

[jlittle]

DejaVu Serif works for me, including in Synaptic.