QT apps have no text in Ubuntu Mate

I'm running a Mate session on Ubuntu 24.04.4, and noticed that text is missing from all QT applications. The widgets, geometry, theme, is there, but no text. - It's not just text [missing](https://forum.videolan.org/viewtopic.php?t=25121) from [menus](https://forum.videolan.org/viewtopic.php?t=24293) , this is a different bug. - It might be similar to [this issue](https://forum.manjaro.org/t/text-not-visible-in-qt-applications/41488) , but even if I install kvantum settings, I can't use it, because kvantum settings also renders no text. - It feels a bit like [this issue](https://stackoverflow.com/questions/42722746/qt-program-have-no-text-and-i-havent-font-error) , but that was on Raspian and ultimately attributed to QT build options. We know distro packages are built correctly. I'm running a Mate session on Ubuntu 22.04.4, and noticed that none of the QT apps can draw their UI components. The geometry is there but text is missing entirely. - Installing qt6-base-dev and the various packages it pulls in changed nothing. - Installing qt6-wayland and the various packages it pulls in changed nothing. - All available qt*-gtk* packages are installed. I assume it's a font problem? Not sure; Slightly surprised the package manager doesn't sort it out. Apt-reinstalling the affected applications does nothing. How can I fix this? **Edit:** I found only one [forum post](https://ubuntuforums.org/archive/index.php/t-1153331.html) describing a similar issue. The solution involves qtconfig, which does not exist for QT5. [This Reddit thread](https://old.reddit.com/r/voidlinux/comments/hk4ayk/qtconfig_missing/) says to use qt5ct, but I cannot because this is a QT GUI application and therefore its interface does not render. It seems the next step is to find a command-line way to set the *plastique* GUI style for QT5?