Does this software name a specific font package under Ubuntu 18.04? Many fonts are usually available which are not installed by default, so it is probably as simple as issuing the proper apt-get install command if you know of a package name. Drivers and fonts are very separate topics and there is no indication that drivers are involved in any way with a missing font. Basically, I think this is just a font issue and is unrelated to specific hardware or drivers…drivers simply display what they are told, but if it doesn’t know the shape of the font, it can’t display it.