--- a/mercurial/configitems.py Tue Nov 23 17:52:38 2021 -0800 +++ b/mercurial/configitems.py Fri Nov 26 16:51:58 2021 +0100 @@ -1281,7 +1281,7 @@ ) coreconfigitem( b'extensions', - b'.*', + b'[^:]*', default=None, generic=True, )