Configuration File¶
Portal backends are selected and can be configured by using one or more configuration files.
Desktop systems may have multiple desktop environments and portal backends installed in parallel, and automatically picking portal backends in this situation has proven to be a challenge.
For this reason, XDG Desktop Portal uses a config-based matching system. Usually, the configuration files are provided by the desktop environments themselves, so that e.g. the GNOME-specific portal backends are picked in GNOME sessions. No end user intervention is necessary in this case.
Here’s an example of a config file distributed by GNOME:
[preferred]
default=gnome;gtk;
org.freedesktop.impl.portal.Access=gnome-shell;gtk;
org.freedesktop.impl.portal.Secret=gnome-keyring;
This file specifies that, by default, the gnome and gtk portal backends
must be used. However, specifically for org.freedesktop.impl.portal.Access, the gnome-shell and gtk
portal backends must be used; and for org.freedesktop.impl.portal.Secret, the gnome-keyring portal
backend must be used.
You can read more about the config file syntax, install locations, and more, in the portals.conf man page: