xdg-desktop-portal 1.17.x introduces a new way to select which portals will
be used for which desktop environments, modelled on mimeapps.list:
- each desktop environment should provide a file like
/usr/share/xdg-desktop-portal/lxde-portals.conf
- the filename is ${DESKTOP}-portals.conf where ${DESKTOP} is the desktop
environment's entry in $XDG_CURRENT_DESKTOP (the same as the DesktopNames
from /usr/share/{x,wayland-}sessions/*.desktop), folded to lower case
- sysadmins and users can override this via files named portals.conf or
${DESKTOP}-portals.conf in various locations like /etc/xdg-desktop-portal
and ~/.config/xdg-desktop-portal
Please see portals.conf(5) or its source code
https://github.com/flatpak/xdg-desktop-portal/blob/main/doc/portals-conf.rst
for full details.
As a backwards-compatibility mechanism, x-d-p will fall back to trying
to guess the most appropriate portals from the portals' UseIn= fields,
but it will log warnings when it does that, and anyway Debian doesn't
currently ship any portal backends that are flagged as suitable for LXDE
(https://github.com/lxqt/xdg-desktop-portal-lxqt exists, but I couldn't
find an ITP for it). Please add an lxde-portals.conf to tell x-d-p more
explicitly what backends LXDE is meant to be using by default.
For example, if the intention is to try to use the -lxqt backend, falling
back to -gtk if -lxqt isn't installed or doesn't know how to do something,
the way to write that would be:
[preferred]
default=lxqt;gtk;
The desktop environment (either openbox-lxde-session or some larger
metapackage) should probably also have a Recommends, or at least a
Suggests, on whatever portals would be most appropriate for it.
Thanks,
smcv