[ie/youtube:tab] Fix playlist continuation extraction (#12777)

Fixes https://github.com/yt-dlp/yt-dlp/issues/12759

Authored by: coletdjnz

yt_dlp/extractor/youtube/_base.py

@@ -803,12 +803,14 @@ class YoutubeBaseInfoExtractor(InfoExtractor):
 
     @classmethod
     def _extract_continuation_ep_data(cls, continuation_ep: dict):
-        if isinstance(continuation_ep, dict):
-            continuation = try_get(
-                continuation_ep, lambda x: x['continuationCommand']['token'], str)
+        continuation_commands = traverse_obj(
+            continuation_ep, ('commandExecutorCommand', 'commands', ..., {dict}))
+        continuation_commands.append(continuation_ep)
+        for command in continuation_commands:
+            continuation = traverse_obj(command, ('continuationCommand', 'token', {str}))
             if not continuation:
-                return
-            ctp = continuation_ep.get('clickTrackingParams')
+                continue
+            ctp = command.get('clickTrackingParams')
             return cls._build_api_continuation_query(continuation, ctp)
 
     @classmethod