Xrdp is a free and open-source implementation of Microsoft RDP (Remote Desktop Protocol) other than Microsoft Windows (such as Linux and BSD-style operating systems) to provide a fully functional RDP-compatible remote desktop experience.

wikipedia.org/wiki/Xrdp

INCLUDE options/network.makejail
INCLUDE gh+AppJail-makejails/xrdp

OPTION expose=3389
OPTION template=files/xrdp.conf

CMD pw useradd -n op -m
CMD passwd op

Where options/network.makejail are the options that suit your environment, for example:

ARG network
ARG interface=xrdp

OPTION virtualnet=${network}:${interface} default
OPTION nat

The files/xrdp.conf template is as follows:

exec.start: "/bin/sh /etc/rc"
exec.stop: "/bin/sh /etc/rc.shutdown jail"
mount.devfs
sysvmsg: new
sysvsem: new
sysvshm: new

Open a shell and run appjail makejail:

appjail makejail -j xrdp -- --network home

• xrdp_tag (default: 13.4): see #tags.