HelenOS sources

menu_frame_h_margin_text  311 uspace/lib/ui/src/menu.c 	rect.p0.x += menu_frame_h_margin_text;
menu_frame_h_margin_text  312 uspace/lib/ui/src/menu.c 	rect.p1.x -= menu_frame_h_margin_text;
HelenOS homepage, sources at GitHub