diff --git a/fmt/Bean2External.cpp b/fmt/Bean2External.cpp
index f6bb100..94979aa 100644
--- a/fmt/Bean2External.cpp
+++ b/fmt/Bean2External.cpp
@@ -92,10 +92,15 @@ namespace NekoRay::fmt {
             auto config = config_simple;
             config = config.replace("%mapping_port%", Int2String(mapping_port));
             config = config.replace("%socks_port%", Int2String(socks_port));
+            config = config.replace("%server_addr%", serverAddress);
+            config = config.replace("%server_port%", Int2String(serverPort));
 
-            // trojan-go: unsupported config format: xxx.tmp. use .yaml or .json instead.
-            auto suffix = ".tmp";
-            if (!QString2QJsonObject(config).isEmpty()) {
+            // suffix
+            QString suffix;
+            if (!config_suffix.isEmpty()) {
+                suffix = "." + config_suffix;
+            } else if (!QString2QJsonObject(config).isEmpty()) {
+                // trojan-go: unsupported config format: xxx.tmp. use .yaml or .json instead.
                 suffix = ".json";
             }
 
diff --git a/fmt/CustomBean.hpp b/fmt/CustomBean.hpp
index 2d62a1d..164b836 100644
--- a/fmt/CustomBean.hpp
+++ b/fmt/CustomBean.hpp
@@ -7,14 +7,14 @@ namespace NekoRay::fmt {
     public:
         QString core;
         QList<QString> command;
-//        QString config_map; // map: fn to text
+        QString config_suffix;
         QString config_simple;
 
         CustomBean() : AbstractBean(0) {
             _add(new configItem("core", &core, itemType::string));
             _add(new configItem("cmd", &command, itemType::stringList));
-//            _add(new configItem("cm", &config_map, itemType::string));
             _add(new configItem("cs", &config_simple, itemType::string));
+            _add(new configItem("cs_suffix", &config_suffix, itemType::string));
         };
 
         QString DisplayType() override {
diff --git a/translations/zh_CN.ts b/translations/zh_CN.ts
index f4a9a84..d7099ad 100644
--- a/translations/zh_CN.ts
+++ b/translations/zh_CN.ts
@@ -599,6 +599,10 @@
         <source>Please read the documentation. If you don&apos;t understand, use a share link instead.</source>
         <translation>格式请看文档。如果不懂，直接导入 hysteria:// 链接。</translation>
     </message>
+    <message>
+        <source>Config Suffix</source>
+        <translation>配置文件后缀</translation>
+    </message>
 </context>
 <context>
     <name>EditNaive</name>
diff --git a/ui/edit/edit_custom.cpp b/ui/edit/edit_custom.cpp
index ddc1855..cd59766 100644
--- a/ui/edit/edit_custom.cpp
+++ b/ui/edit/edit_custom.cpp
@@ -50,6 +50,7 @@ void EditCustom::onStart(QSharedPointer<NekoRay::ProxyEntity> _ent) {
     P_LOAD_COMBO(core)
     ui->command->setText(bean->command.join(" "));
     P_LOAD_STRING(config_simple)
+    P_LOAD_COMBO(config_suffix)
 
     // custom external
     if (!bean->core.isEmpty()) {
@@ -68,6 +69,8 @@ void EditCustom::onStart(QSharedPointer<NekoRay::ProxyEntity> _ent) {
         ui->core_l->setText(tr("Outbound JSON, please read the documentation."));
         ui->command->hide();
         ui->command_l->hide();
+        ui->config_suffix->hide();
+        ui->config_suffix_l->hide();
     }
 
     // Generators
@@ -80,6 +83,7 @@ bool EditCustom::onEnd() {
     P_SAVE_COMBO(core)
     bean->command = ui->command->text().split(" ");
     P_SAVE_STRING_QTEXTEDIT(config_simple)
+    P_SAVE_COMBO(config_suffix)
 
     if (bean->core.isEmpty()) {
         MessageBoxWarning(software_name, tr("Please pick a core."));
diff --git a/ui/edit/edit_custom.ui b/ui/edit/edit_custom.ui
index a001bfa..4882542 100644
--- a/ui/edit/edit_custom.ui
+++ b/ui/edit/edit_custom.ui
@@ -63,6 +63,30 @@
          </property>
         </widget>
        </item>
+       <item>
+        <widget class="QLabel" name="config_suffix_l">
+         <property name="text">
+          <string>Config Suffix</string>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <widget class="QComboBox" name="config_suffix">
+         <property name="editable">
+          <bool>true</bool>
+         </property>
+         <item>
+          <property name="text">
+           <string notr="true"/>
+          </property>
+         </item>
+         <item>
+          <property name="text">
+           <string notr="true">json</string>
+          </property>
+         </item>
+        </widget>
+       </item>
       </layout>
      </item>
      <item>