Some users of our application are asking to increase the font size. In Tryton4 + GTK2 we used the file \etc\gtk-2.0\gtkrc for this purpose. In Tryton5 + GTK3 we have tried to use the file \etc\gtk-3.0\settings.ini: [Settings] gtk-font-name=Sans 10 But this does not work. What are we doing wrong? …

P.S. With our solution bold and italic font-styles are gone. So it is better to use the following file ~\.config\tryton\5.2\theme.css: box * { font-size: 12px; }