diff --git a/dot_config/xdg-desktop-portal/sway-portals.conf b/dot_config/xdg-desktop-portal/sway-portals.conf
new file mode 100644
index 0000000..acbaeac
--- /dev/null
+++ b/dot_config/xdg-desktop-portal/sway-portals.conf
@@ -0,0 +1,14 @@
+# 2025-04-02: copied from /usr/share/xdg-desktop-portal/sway-portals.conf
+[preferred]
+default=gtk
+org.freedesktop.impl.portal.ScreenCast=wlr
+org.freedesktop.impl.portal.Screenshot=wlr
+# xdg-desktop-portal-gtk's implementation uses org.gnome.SessionManager and
+# org.freedesktop.ScreenSaver, neither of which is implemented by Sway. This
+# will cause some programs (e.g. Firefox) to use Wayland's idle-inhibit
+# protocol instead, which sway does implement.
+org.freedesktop.impl.portal.Inhibit=none
+
+# 2025-04-02: needed for GTK applications?
+# See: https://gitlab.com/WhyNotHugo/darkman/-/issues/65
+org.freedesktop.impl.portal.Settings=darkman