Hi!
I see this topic is already old, but the problem with the icons still remains.
I've tried on MATE to change the size of the windows to HiDPI, and while it works with other softwares (like LibreOffice), the size of the Scribus icons remains the same (I've tried to use gtk2 als theme, without succes). That's kind of problematic when using a big screen.
Does anyone know another solution? Maybe changing the icons themselfs in their folder?
I would thank your creativity!