diff --git a/packages/backend/src/server/web/boot.js b/packages/backend/src/server/web/boot.js
index 396536948e..5e59a51ed9 100644
--- a/packages/backend/src/server/web/boot.js
+++ b/packages/backend/src/server/web/boot.js
@@ -174,7 +174,7 @@
 			<p>Update your os and browser / ブラウザおよびOSを最新バージョンに更新する</p>
 			<p>Disable an adblocker / アドブロッカーを無効にする</p>
 	 		<p>&#40;Tor Browser&#41; Set dom.webaudio.enabled to true / dom.webaudio.enabledをtrueに設定する</p>
-			<details style="color: #86b300;">
+			<details class="hide-when-embed" style="color: #86b300;">
 				<summary>Other options / その他のオプション</summary>
 				<a href="/flush">
 					<button class="button-small">
@@ -228,6 +228,10 @@
 			text-align: center;
 		}
 
+		html.embed .hide-when-embed {
+			display: none;
+		}
+
 		button {
 			border-radius: 999px;
 			padding: 0px 12px 0px 12px;
diff --git a/packages/backend/src/server/web/views/base.pug b/packages/backend/src/server/web/views/base.pug
index 897481d369..51b868cd1b 100644
--- a/packages/backend/src/server/web/views/base.pug
+++ b/packages/backend/src/server/web/views/base.pug
@@ -17,7 +17,7 @@ doctype html
 	 https://github.com/misskey-dev/misskey
 
 
-html
+html(class=embed && 'embed')
 
 	head
 		meta(charset='utf-8')
@@ -77,7 +77,7 @@ html
 		script
 			include ../boot.js
 
-	body(class=embed && 'embed')
+	body
 		noscript: p
 			| JavaScriptを有効にしてください
 			br