Issue #4213: The file system encoding is now normalized by the codec subsystem, for example UTF-8 is turned into utf-8.
Patch created by Victor and reviewed by me. The change is required for proper initialization of subinterpreters.
diff --git a/Misc/NEWS b/Misc/NEWS
index 20359ff..72a482e 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -15,6 +15,9 @@
Core and Builtins
-----------------
+- Issue #4213: The file system encoding is now normalized by the
+ codec subsystem, for example UTF-8 is turned into utf-8.
+
- Issue #4200: Changed the atexit module to store its state in its
PyModuleDef atexitmodule. This fixes a bug with multiple subinterpeters.