The panel of my computer has a resolution of 3840 x 2160 pixels. If I open a gnome-boxes session, the code of the virtual machine occupies a space little bigger than a postage stamp. GNOME-Boxes reports that I'm seeing 1920 x 1080 pixels. The following picture shows the gnome-blocks desktop.
Full-screen view of GNOME Boxes with one virtual machine showing.
Does anyone know how to increase the size of the displayed box?