diff --git a/src/main/assemblies/extension/fess-ss/form.html b/src/main/assemblies/extension/fess-ss/form.html
index 50544b796..df2c97727 100644
--- a/src/main/assemblies/extension/fess-ss/form.html
+++ b/src/main/assemblies/extension/fess-ss/form.html
@@ -1,4 +1,9 @@
-<html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+</head>
 
 <script>
   (function() {
diff --git a/src/main/assemblies/extension/fess-ss/result.html b/src/main/assemblies/extension/fess-ss/result.html
index c0cc4a4c3..492d6c065 100644
--- a/src/main/assemblies/extension/fess-ss/result.html
+++ b/src/main/assemblies/extension/fess-ss/result.html
@@ -1,4 +1,9 @@
-<html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+</head>
 
 <script>
   (function() {
diff --git a/src/main/assemblies/extension/fess-ss/ss.html b/src/main/assemblies/extension/fess-ss/ss.html
index 5d5c88b9a..f4da17a48 100644
--- a/src/main/assemblies/extension/fess-ss/ss.html
+++ b/src/main/assemblies/extension/fess-ss/ss.html
@@ -1,4 +1,9 @@
-<html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+</head>
 
 <script>
   (function() {
