diff --git a/yt_dlp/extractor/youtube/_base.py b/yt_dlp/extractor/youtube/_base.py
index 64980650ec..5ccafff57a 100644
--- a/yt_dlp/extractor/youtube/_base.py
+++ b/yt_dlp/extractor/youtube/_base.py
@@ -306,7 +306,8 @@ INNERTUBE_CLIENTS = {
             'client': {
                 'clientName': 'TVHTML5',
                 'clientVersion': '7.20250312.16.00',
-                'userAgent': 'Mozilla/5.0 (ChromiumStylePlatform) Cobalt/Version',
+                # See: https://github.com/youtube/cobalt/blob/main/cobalt/browser/user_agent/user_agent_platform_info.cc#L506
+                'userAgent': 'Mozilla/5.0 (ChromiumStylePlatform) Cobalt/25.lts.30.1034943-gold (unlike Gecko), Unknown_TV_Unknown_0/Unknown (Unknown, Unknown)',
             },
         },
         'INNERTUBE_CONTEXT_CLIENT_NAME': 7,