diff -r e45c6b153e51 -r ce5f1232631f mercurial/sslutil.py
--- a/mercurial/sslutil.py	Mon May 06 22:10:34 2019 -0400
+++ b/mercurial/sslutil.py	Wed May 08 16:09:50 2019 -0400
@@ -722,7 +722,7 @@
         certs = certifi.where()
         if os.path.exists(certs):
             ui.debug('using ca certificates from certifi\n')
-            return certs
+            return pycompat.fsencode(certs)
     except (ImportError, AttributeError):
         pass