From c54d93ba5f94c9687c7b3015683c292e2e4b37a4 Mon Sep 17 00:00:00 2001
From: tmk3ki <tmk.33ki@gmail.com>
Date: Wed, 22 Jul 2026 11:35:45 +0900
Subject: [PATCH] =?UTF-8?q?=E5=AE=9F=E6=B3=81=E3=83=A2=E3=83=BC=E3=83=89:?=
 =?UTF-8?q?=20=E9=9F=B3=E5=A3=B0=E3=83=88=E3=83=A9=E3=83=83=E3=82=AF?=
 =?UTF-8?q?=E3=81=8C=E5=8F=96=E5=BE=97=E3=81=A7=E3=81=8D=E3=81=A6=E3=81=84?=
 =?UTF-8?q?=E3=81=AA=E3=81=84=E5=A0=B4=E5=90=88=E3=81=AB=E8=AD=A6=E5=91=8A?=
 =?UTF-8?q?(macOS=E3=81=AF=E7=94=BB=E9=9D=A2/=E3=82=A6=E3=82=A3=E3=83=B3?=
 =?UTF-8?q?=E3=83=89=E3=82=A6=E5=85=B1=E6=9C=89=E3=81=A0=E3=81=A8=E7=84=A1?=
 =?UTF-8?q?=E9=9F=B3=E3=81=AB=E3=81=AA=E3=82=8B=E3=81=9F=E3=82=81)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 web/index.html | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/web/index.html b/web/index.html
index 53c3df6..66633ca 100644
--- a/web/index.html
+++ b/web/index.html
@@ -611,6 +611,12 @@ async function startWatchMode() {
     console.error('getDisplayMedia failed', e);
     return;
   }
+  if (watchStream.getAudioTracks().length === 0) {
+    alert('音声トラックが取得できませんでした。共有元は「Chromeタブ」を選び、「タブの音声を共有」にチェックを入れ直してください(画面全体/ウィンドウ共有だとmacOSでは音声が乗りません)。');
+    watchStream.getTracks().forEach((t) => t.stop());
+    watchStream = null;
+    return;
+  }
   watchActive = true;
   updateWatchButton();
   watchStream.getVideoTracks()[0].addEventListener('ended', stopWatchMode);