# # xdg-utils portal interaction: for `xdg-open` to open a file whose handler may require files not in the current sandbox,
# # we have to use a background service. that's achieved via `xdg-desktop-portal` and the org.freedesktop.portal.OpenURI dbus interface.
# # so, this `xdg-open` should simply forward all requests to the portal, and the portal may re-invoke xdg-open without that redirection.
# # -- EXCEPT for if we're invoked by the portal itself.
# #
# # note that `xdg-desktop-portal` seems to (inadvertently) only accept requests from applications which *don't* have elevated privileges, hence xdg-open *has* to be sandboxed for this to work.