diff --git a/phpBB/includes/ucp/ucp_notifications.php b/phpBB/includes/ucp/ucp_notifications.php
index b0eeb915ec..7a46d3e5aa 100644
--- a/phpBB/includes/ucp/ucp_notifications.php
+++ b/phpBB/includes/ucp/ucp_notifications.php
@@ -62,6 +62,7 @@ class ucp_notifications
 							foreach ($notification_methods as $method => $method_data)
 							{
 								$is_set_notify = $request->is_set_post(str_replace('.', '_', $type . '_' . $method_data['id']));
+								$is_available = $method_data['method']->is_available($type_data['type']);
 
 								/**
 								* Event to perform additional actions before ucp_notifications is submitted
@@ -70,21 +71,26 @@ class ucp_notifications
 								* @var	array	type_data		The notification type data
 								* @var	array	method_data		The notification method data
 								* @var	bool	is_set_notify	The notification is set or not
+								* @var	bool	is_available	The notification is available or not
+								* @var	array	subscriptions	The subscriptions data
 								*
 								* @since 3.2.10-RC1
+								* @since 3.3.1-RC1
 								*/
 								$vars = [
 									'type_data',
 									'method_data',
 									'is_set_notify',
+									'is_available',
+									'subscriptions',
 								];
 								extract($phpbb_dispatcher->trigger_event('core.ucp_notifications_submit_notification_is_set', compact($vars)));
 
-								if ($is_set_notify && (!isset($subscriptions[$type]) || !in_array($method_data['id'], $subscriptions[$type])))
+								if ($is_set_notify && $is_available && (!isset($subscriptions[$type]) || !in_array($method_data['id'], $subscriptions[$type])))
 								{
 									$phpbb_notifications->add_subscription($type, 0, $method_data['id']);
 								}
-								else if (!$is_set_notify && isset($subscriptions[$type]) && in_array($method_data['id'], $subscriptions[$type]))
+								else if ((!$is_set_notify || !$is_available) && isset($subscriptions[$type]) && in_array($method_data['id'], $subscriptions[$type]))
 								{
 									$phpbb_notifications->delete_subscription($type, 0, $method_data['id']);
 								}
@@ -225,13 +231,16 @@ class ucp_notifications
 					* @var	array	type_data		The notification type data
 					* @var	array	method_data		The notification method data
 					* @var	array	tpl_ary			The template variables
+					* @var	array	subscriptions	The subscriptions data
 					*
 					* @since 3.2.10-RC1
+					* @since 3.3.1-RC1
 					*/
 					$vars = [
 						'type_data',
 						'method_data',
 						'tpl_ary',
+						'subscriptions',
 					];
 					extract($phpbb_dispatcher->trigger_event('core.ucp_notifications_output_notification_types_modify_template_vars', compact($vars)));
 
diff --git a/phpBB/phpbb/notification/manager.php b/phpBB/phpbb/notification/manager.php
index 2d6d081d33..ace08e6cf6 100644
--- a/phpBB/phpbb/notification/manager.php
+++ b/phpBB/phpbb/notification/manager.php
@@ -350,6 +350,7 @@ class manager
 		* @var	array 	notify_users				User list to notify
 		*
 		* @since 3.2.10-RC1
+		* @since 3.3.1-RC1
 		*/
 		$vars = [
 			'notification_type_name',
diff --git a/phpBB/styles/prosilver/template/ucp_notifications.html b/phpBB/styles/prosilver/template/ucp_notifications.html
index 8be157c933..7ebe6d431a 100644
--- a/phpBB/styles/prosilver/template/ucp_notifications.html
+++ b/phpBB/styles/prosilver/template/ucp_notifications.html
@@ -31,7 +31,7 @@
 								<!-- IF notification_types.EXPLAIN --><br />&nbsp; &nbsp;{notification_types.EXPLAIN}<!-- ENDIF -->
 							</td>
 							<!-- BEGIN notification_methods -->
-								<td class="mark"><input type="checkbox" name="{notification_types.TYPE}_{notification_types.notification_methods.METHOD}"<!-- IF notification_types.notification_methods.AVAILABLE and notification_types.notification_methods.SUBSCRIBED --> checked="checked"<!-- ENDIF --><!-- IF not notification_types.notification_methods.AVAILABLE --> disabled="disabled"<!-- ENDIF --> /></td>
+								<td class="mark"><input type="checkbox" name="{notification_types.TYPE}_{notification_types.notification_methods.METHOD}"<!-- IF notification_types.notification_methods.SUBSCRIBED --> checked="checked"<!-- ENDIF --><!-- IF not notification_types.notification_methods.AVAILABLE --> disabled="disabled"<!-- ENDIF --> /></td>
 							<!-- END notification_methods -->
 						</tr>
 					<!-- ENDIF -->
diff --git a/phpBB/ucp.php b/phpBB/ucp.php
index f11a542703..817ea72111 100644
--- a/phpBB/ucp.php
+++ b/phpBB/ucp.php
@@ -365,6 +365,7 @@ if ($module->is_active('zebra', 'friends'))
 	* @var	array	sql_ary		SQL query array for listing of friends
 	*
 	* @since 3.2.10-RC1
+	* @since 3.3.1-RC1
 	*/
 	$vars = [
 		'sql_ary',
@@ -395,6 +396,7 @@ if ($module->is_active('zebra', 'friends'))
 		* @var	string	which		friend is 'online' or 'offline'
 		*
 		* @since 3.2.10-RC1
+		* @since 3.3.1-RC1
 		*/
 		$vars = [
 			'row',
diff --git a/phpBB/viewforum.php b/phpBB/viewforum.php
index 14c3ba1409..db88faabb0 100644
--- a/phpBB/viewforum.php
+++ b/phpBB/viewforum.php
@@ -723,6 +723,7 @@ if (count($topic_list))
 	* @var	array	sql_array			SQL query array for obtaining topics/stickies
 	*
 	* @since 3.2.10-RC1
+	* @since 3.3.1-RC1
 	*/
 	$vars = [
 		'forum_id',