I think it’s a qemu inside stubdomain:
gui-emulated
Qube provides GUI through emulated VGA. Setting this feature to
True
enables emulated VGA output. Note that when gui-agent connects to actual VM, emulated VGA output is closed (unless debug property is set toTrue
). It’s possible to open emulated VGA output for a running qube, regardless of this feature, using qvm-start-daemon –force-stubdomain QUBE_NAME command.This feature is applicable only when qube’s virt_mode is set to hvm. See also gui feature.
If neither gui nor gui-emulated is set, emulated VGA is used (if applicable for given VM virtualization mode).
linux-stubdom
Use Linux-based stubdomain for running device model (qemu). This makes use of recent qemu upstream version. If disabled, use MiniOS-based stubdomain with old qemu fork (aka qemu-traditional). This applies only to hvm virt_mode, for other modes it is ignored.
Default: True
https://dev.qubes-os.org/projects/core-admin-client/en/stable/manpages/qvm-features.html