I'm running a up-to-date mate openrc installation installed from the mate-release-iso.
When using htop in a MATE Terminal, the graphs are broken:

I'm pretty sure thats a font issue, but i don't manage to get it fixed. No matter what terminal font i use.
Any hints?
I can't tell you which font but yes that is a font issues, you can try installing the bitstream-vera fonts and noto fonts(i they aren't already)
You are the man, installing noto-fonts fixed it.