diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index 598a399b93..7e49d8e267 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -3136,6 +3136,9 @@ StandardInputData=V2XigLJyZSBubyBzdHJhbmdlcnMgdG8gbG92ZQpZb3Uga25vdyB0aGUgcnVsZX
         values are indexed may also be used to implement cross-unit log record matching. Assign an empty
         string to reset the list.</para>
 
+        <para>Note that this functionality is currently only available in system services, not in per-user
+        services.</para>
+
         <xi:include href="version-info.xml" xpointer="v236"/></listitem>
       </varlistentry>
 
@@ -3191,6 +3194,9 @@ StandardInputData=V2XigLJyZSBubyBzdHJhbmdlcnMgdG8gbG92ZQpZb3Uga25vdyB0aGUgcnVsZX
         the kernel log buffer (kmsg), the systemd console, or sent as wall messages to all logged-in
         users.</para>
 
+        <para>Note that this functionality is currently only available in system services, not in per-user
+        services.</para>
+
         <xi:include href="version-info.xml" xpointer="v253"/></listitem>
       </varlistentry>