GNOME Boxes gets Flatpak-only rewrite, GTK4 UI and Windows 11 support

Developer Felipe Borges, who also works at Red Hat, has released a beta version of GNOME Boxes that is rebuilt as a Flatpak‑only application. By bundling the full libvirt/QEMU virtualization stack inside the Flatpak, the new Boxes no longer depends on host distribution packages, simplifying maintenance for a solo maintainer.

The rewrite moves the interface to GTK4 and Libadwaita, replacing the legacy GTK3 SPICE widget with a new Libmks display component. This modern UI brings a refreshed look and tighter desktop integration. The updated Boxes can now install Windows 11 automatically, configuring Secure Boot and a virtual TPM without user intervention, and it includes a VSOCK device that enables direct SSH connections to guests running systemd v256 or newer. Early port‑forwarding support for SSH and HTTP is also available.

The release is labeled a beta for testing only; users are advised to back up virtual‑machine data before trying it in production environments.