xdg-desktop-portal is a portal frontend service for Flatpak and possibly other
desktop containment frameworks.

xdg-desktop-portal works by exposing a series of D-Bus interfaces known as
_portals_ under a well-known name (org.freedesktop.portal.Desktop) and object
path (/org/freedesktop/portal/desktop).

The portal interfaces include APIs for file access, opening URIs, printing and
others.
