add some explanation and remove logging

Zotlabs/Daemon/Notifier.php

@@ -334,7 +334,6 @@ class Notifier {
 			$m = get_iconfig($target_item, 'activitypub', 'signed_data');
 			// Re-use existing signature unless the activity type changed to a Tombstone, which won't verify.
 			if ($m && (!intval($target_item['item_deleted']))) {
-				hz_syslog('notifier existing');
 				self::$encoded_item = json_decode($m, true);
 			}
 			else {

Zotlabs/Lib/Libzot.php

@@ -1583,6 +1583,11 @@ class Libzot {
 			 * There's a chance the current delivery could take place before the cloned copy arrives
 			 * hence the item could have the wrong ACL and *could* be used in subsequent deliveries or
 			 * access checks.
+			 *
+			 * 30.3.23: block all incoming items from ourselves except if the origin is local.
+			 * This is to prevent multiple relay delivery of items that arrive via sync.
+			 * They have already been relayed at the origin location.
+			 *
 			 */
 
 			if ($sender === $channel['channel_hash'] && $arr['author_xchan'] === $channel['channel_hash'] && !str_starts_with($arr['mid'], z_root())) {