diff --git a/data/gnome-session-restart-dbus.service.in b/data/gnome-session-restart-dbus.service.in
index e90f6bc8f4735ceaa2e123d975bde5fd0b89f2e7..6389c321bb07542f4e72df66ca0081c5decf6232 100644
--- a/data/gnome-session-restart-dbus.service.in
+++ b/data/gnome-session-restart-dbus.service.in
@@ -1,10 +1,11 @@
 [Unit]
 Description=Restart DBus after GNOME Session shutdown
 
-# Allow exit.target to start even if this unit is started with replace-irreversibly
-# Also put it into a slice that doesn't have such implicit dependencies
+# Allow exit.target to start even if this unit is started with replace-irreversibly.
+# For this to work, we also need to be in the root slice.
 DefaultDependencies=no
 
 [Service]
 Type=notify
 ExecStart=@libexecdir@/gnome-session-ctl --restart-dbus
+Slice=-.slice
diff --git a/data/gnome-session-shutdown.target b/data/gnome-session-shutdown.target
index 607dc6e71a322010c66e35e799d39ecad144d1a3..2c3d1963209ee0f23156b7100241ea0809e3534c 100644
--- a/data/gnome-session-shutdown.target
+++ b/data/gnome-session-shutdown.target
@@ -1,8 +1,9 @@
 [Unit]
 Description=Shutdown running GNOME Session
 
-# Allow exit.target to start even if this unit is started with replace-irreversibly
-# The same is needed for all (weak) dependencies
+# Allow exit.target to start even if this unit is started with replace-irreversibly.
+# All (weak) dependencies need to do the same. Services also need to ensure they
+# are in the root slice by setting Slice=-.slice.
 DefaultDependencies=no
 
 Conflicts=graphical-session.target graphical-session-pre.target