diff --git a/TODO b/TODO
index f912645762..216dc9be0d 100644
--- a/TODO
+++ b/TODO
@@ -28,6 +28,8 @@ External:
 
 Features:
 
+* man: document that unless you use StandardError=null the shell >/dev/stderr won't work in shell scripts in services
+
 * man: clarify that "machinectl show" shows different information than "machinectl status" (no cgroup tree, no IP addresses, ...)
 
 * "systemctl daemon-reload" should result in /etc/systemd/system.conf being reloaded by systemd