diff --git a/yt_dlp/downloader/dash.py b/yt_dlp/downloader/dash.py
index 8dd43f4fa..4c23edd32 100644
--- a/yt_dlp/downloader/dash.py
+++ b/yt_dlp/downloader/dash.py
@@ -47,7 +47,7 @@ def real_download(self, filename, info_dict):
             if real_downloader:
                 self.to_screen(
                     '[%s] Fragment downloads will be delegated to %s' % (self.FD_NAME, real_downloader.get_basename()))
-                info_dict['fragments'] = fragments_to_download
+                info_dict['fragments'] = list(fragments_to_download)
                 fd = real_downloader(self.ydl, self.params)
                 return fd.real_download(filename, info_dict)