If you’d like to override the original lv_font_montserrat_22.c file it can be found in lvgl/src/font a modification that’s outside of the reach of SquareLine studio. But it’s better if you create and set a new font in SquareLine Studio and leave LV_FONT_MONTSERRAT_22 at value 0, so the original font won’t get built as an unnecessary duplicate taking memory. (So the preferred way is that you follow in your other opened topic: UI won't load widgets past one with a custom font )