--- a/mercurial/dispatch.py	Thu Feb 02 17:23:20 2023 +0100
+++ b/mercurial/dispatch.py	Thu Feb 02 17:23:31 2023 +0100
@@ -116,7 +116,7 @@
             err = e
             status = -1
 
-    if util.safehasattr(ui, b'ferr'):
+    if util.safehasattr(ui, 'ferr'):
         assert ui is not None  # help pytype
         assert ui.ferr is not None  # help pytype
         try: