diff --git a/makespec/BUILDVERSION b/makespec/BUILDVERSION
index 76674f15..b26d474a 100644
--- a/makespec/BUILDVERSION
+++ b/makespec/BUILDVERSION
@@ -1 +1 @@
-5568
+5569
diff --git a/src/components/plugins/QvPluginHost.cpp b/src/components/plugins/QvPluginHost.cpp
index 64ed94b8..c84ca838 100644
--- a/src/components/plugins/QvPluginHost.cpp
+++ b/src/components/plugins/QvPluginHost.cpp
@@ -279,7 +279,7 @@ namespace Qv2ray::components::plugins
             if (plugin.isLoaded && plugin.metadata.SpecialPluginType.contains(SPECIAL_TYPE_SERIALIZOR))
             {
                 auto serializer = plugin.pluginInterface->GetSerializer();
-                if (serializer->OutboundProtocols().contains(protocol))
+                if (serializer && serializer->OutboundProtocols().contains(protocol))
                 {
                     auto info = serializer->GetOutboundInfo(protocol, o);
                     *status = true;
@@ -301,7 +301,7 @@ namespace Qv2ray::components::plugins
             if (plugin.isLoaded && plugin.metadata.SpecialPluginType.contains(SPECIAL_TYPE_SERIALIZOR))
             {
                 auto serializer = plugin.pluginInterface->GetSerializer();
-                if (serializer->OutboundProtocols().contains(protocol))
+                if (serializer && serializer->OutboundProtocols().contains(protocol))
                 {
                     auto link = serializer->SerializeOutbound(protocol, alias, groupName, outboundSettings);
                     *status = true;
diff --git a/src/plugin-interface b/src/plugin-interface
index 9f305d4f..8425a473 160000
--- a/src/plugin-interface
+++ b/src/plugin-interface
@@ -1 +1 @@
-Subproject commit 9f305d4f352c1f28cc53cf39931e12b286fc3f1c
+Subproject commit 8425a473155b8e914a092712495a48978fe63c26
diff --git a/src/ui/windows/w_PreferencesWindow.cpp b/src/ui/windows/w_PreferencesWindow.cpp
index 77586236..8ca55d29 100644
--- a/src/ui/windows/w_PreferencesWindow.cpp
+++ b/src/ui/windows/w_PreferencesWindow.cpp
@@ -325,7 +325,7 @@ void PreferencesWindow::on_buttonBox_accepted()
         }
         SaveGlobalSettings(CurrentConfig);
         UIMessageBus.EmitGlobalSignal(QvMBMessage::UPDATE_COLORSCHEME);
-        if (NeedRestart)
+        if (NeedRestart && !KernelInstance->CurrentConnection().isEmpty())
         {
             this->setEnabled(false);
             qApp->processEvents();