diff --git a/plinth/modules/upgrades/data/usr/lib/systemd/system/freedombox-manual-upgrade.service b/plinth/modules/upgrades/data/usr/lib/systemd/system/freedombox-manual-upgrade.service
index c0f80714c..a85b20a1a 100644
--- a/plinth/modules/upgrades/data/usr/lib/systemd/system/freedombox-manual-upgrade.service
+++ b/plinth/modules/upgrades/data/usr/lib/systemd/system/freedombox-manual-upgrade.service
@@ -1,5 +1,6 @@
 [Unit]
 Description=Run unattended-upgrade once
+Documentation=https://wiki.debian.org/FreedomBox/Manual/Upgrades
 
 [Service]
 Type=oneshot