diff --git a/apps/advanced/backend/views/layouts/main.php b/apps/advanced/backend/views/layouts/main.php
index e3f294fa0e..f046488f6b 100644
--- a/apps/advanced/backend/views/layouts/main.php
+++ b/apps/advanced/backend/views/layouts/main.php
@@ -14,7 +14,7 @@ AppAsset::register($this);
 <!DOCTYPE html>
 <html lang="<?= Yii::$app->language ?>">
 <head>
-    <meta charset="<?= Yii::$app->charset ?>"/>
+    <meta charset="<?= Yii::$app->charset ?>">
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <?= Html::csrfMetaTags() ?>
     <title><?= Html::encode($this->title) ?></title>
diff --git a/apps/advanced/frontend/views/layouts/main.php b/apps/advanced/frontend/views/layouts/main.php
index d4e68e6ff6..39d55bdb16 100644
--- a/apps/advanced/frontend/views/layouts/main.php
+++ b/apps/advanced/frontend/views/layouts/main.php
@@ -15,7 +15,7 @@ AppAsset::register($this);
 <!DOCTYPE html>
 <html lang="<?= Yii::$app->language ?>">
 <head>
-    <meta charset="<?= Yii::$app->charset ?>"/>
+    <meta charset="<?= Yii::$app->charset ?>">
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <?= Html::csrfMetaTags() ?>
     <title><?= Html::encode($this->title) ?></title>
