diff --git a/Zotlabs/Daemon/Thumbnail.php b/Zotlabs/Daemon/Thumbnail.php
index e1f17c304..793ed088f 100644
--- a/Zotlabs/Daemon/Thumbnail.php
+++ b/Zotlabs/Daemon/Thumbnail.php
@@ -7,15 +7,17 @@ class Thumbnail {
 
 	static public function run($argc,$argv) {
 
-		if(! $argc == 2)
+		if (! ($argc == 2)) {
 			return;
+		}
 
 		$c = q("select * from attach where hash = '%s' ",
 			dbesc($argv[1])
 		);
 
-		if(! $c)
+		if (! $c) {
 			return;
+		}
 
 		$attach = $c[0];
 
@@ -41,35 +43,34 @@ class Thumbnail {
 		 */
 
 		call_hooks('thumbnail',$p);
-		if($p['thumbnail']) {
+		if ($p['thumbnail']) {
 			return;
 		}
 
-
 		$default_controller = null;
 		
 		$files = glob('Zotlabs/Thumbs/*.php');
-		if($files) {
-			foreach($files as $f) {
+		if ($files) {
+			foreach ($files as $f) {
 				$clsname = '\\Zotlabs\\Thumbs\\' . ucfirst(basename($f,'.php'));
-				if(class_exists($clsname)) {
+				if (class_exists($clsname)) {
 					$x = new $clsname();
-					if(method_exists($x,'Match')) {
+					if (method_exists($x,'Match')) {
 						$matched = $x->Match($attach['filetype']);
-						if($matched) {
+						if ($matched) {
 							$x->Thumb($attach,$preview_style,$preview_width,$preview_height);
 						}
 					}
-					if(method_exists($x,'MatchDefault')) {
+					if (method_exists($x,'MatchDefault')) {
 						$default_matched = $x->MatchDefault(substr($attach['filetype'],0,strpos($attach['filetype'],'/')));
-						if($default_matched) {
+						if ($default_matched) {
 							$default_controller = $x;
 						}
 					}
 				}
 			}
 		}
-		if(($default_controller) 
+		if (($default_controller) 
 			&& ((! file_exists(dbunescbin($attach['content']) . '.thumb')) 
 				|| (filectime(dbunescbin($attach['content']) . 'thumb') < (time() - 60)))) {
 			$default_controller->Thumb($attach,$preview_style,$preview_width,$preview_height);
diff --git a/Zotlabs/Lib/Activity.php b/Zotlabs/Lib/Activity.php
index 6215eaf7f..1b1a393f2 100644
--- a/Zotlabs/Lib/Activity.php
+++ b/Zotlabs/Lib/Activity.php
@@ -2518,6 +2518,9 @@ class Activity {
 				if ((! $allowed) && PConfig::Get($channel['channel_id'], 'system','permit_all_mentions') && i_am_mentioned($channel,$item)) {
 					$allowed = true;
 				}
+				if (absolutely_no_comments($p[0])) {
+					$allowed = false;
+				}
 				
 				if (! $allowed) {
 					logger('rejected comment from ' . $item['author_xchan'] . ' for ' . $channel['channel_address']);
diff --git a/Zotlabs/Lib/Enotify.php b/Zotlabs/Lib/Enotify.php
index fbc144d10..a730d944f 100644
--- a/Zotlabs/Lib/Enotify.php
+++ b/Zotlabs/Lib/Enotify.php
@@ -520,7 +520,7 @@ class Enotify {
 	}
 
 	if (is_array($datarray['parent_item'])) {
-		if (LibBlock::fetch_by_entity($datarray['uid'],$datarray['parent_item']['owner_xchan']) || LibBlock::fetch_by_entity($datarray['uid'],$datarray['parent_item']['owner_xchan'])) {
+		if (LibBlock::fetch_by_entity($datarray['uid'],$datarray['parent_item']['author_xchan']) || LibBlock::fetch_by_entity($datarray['uid'],$datarray['parent_item']['owner_xchan'])) {
 			pop_lang();
 			return;
 		}
diff --git a/Zotlabs/Lib/Libzot.php b/Zotlabs/Lib/Libzot.php
index 7dc4f0da7..b1e180527 100644
--- a/Zotlabs/Lib/Libzot.php
+++ b/Zotlabs/Lib/Libzot.php
@@ -1790,7 +1790,11 @@ class Libzot {
 						$allowed = can_comment_on_post($sender,$parent[0]);
 					}
 					if ((! $allowed) && PConfig::Get($channel['channel_id'], 'system','permit_all_mentions') && i_am_mentioned($channel,$arr)) {
-						$allowed = true;
+						// permit_all_mentions bypasses some comment protections, but if comments are disallowed completely
+						// honour this setting.
+						if (! absolutely_no_comments($arr)) {
+							$allowed = true;
+						}
 					}
 
 				}
diff --git a/include/items.php b/include/items.php
index 5138eda1d..9445604d7 100644
--- a/include/items.php
+++ b/include/items.php
@@ -345,6 +345,26 @@ function can_comment_on_post($observer_xchan, $item) {
 	return false;
 }
 
+
+function absolutely_no_comments($item) {
+
+	if($item['comment_policy'] === 'none') {
+		return true;
+	}
+
+	if (intval($item['item_nocomment'])) {
+		return true;
+	}
+
+	if(comments_are_now_closed($item)) {
+		return true;
+	}
+
+	return false;
+}
+
+
+
 /**
  * @brief Adds $hash to the item source route specified by $iid.
  *