Ensure `mergeall` selects best format when multistreams are disabled

diff --git a/yt_dlp/YoutubeDL.py b/yt_dlp/YoutubeDL.py
index e1ce8c9b30314b10c3ad54a1f239011784c550c7..d7cbdd04736d48c6adba1c9700511ab574cded72 100644 (file)
--- a/yt_dlp/YoutubeDL.py
+++ b/yt_dlp/YoutubeDL.py
@@ -1650,8 +1650,8 @@ def selector_function(ctx):
                         formats = list(ctx['formats'])
                         if not formats:
                             return
-                        merged_format = formats[0]
-                        for f in formats[1:]:
+                        merged_format = formats[-1]
+                        for f in formats[-2::-1]:
                             merged_format = _merge((merged_format, f))
                         yield merged_format