diff --git a/yt_dlp/utils.py b/yt_dlp/utils.py
index 97bd33506a..38aeb6918f 100644
--- a/yt_dlp/utils.py
+++ b/yt_dlp/utils.py
@@ -5489,4 +5489,4 @@ has_websockets = bool(compat_websockets)
 
 def merge_headers(*dicts):
     """Merge dicts of http headers case insensitively, prioritizing the latter ones"""
-    return {k.capitalize(): v for k, v in itertools.chain.from_iterable(map(dict.items, dicts))}
+    return {k.title(): v for k, v in itertools.chain.from_iterable(map(dict.items, dicts))}