used on a utf8 handle used to treat the bytes as utf8, resulting in erratic
behavior (e.g., malformed UTF-8 warnings).
+=item *
+
+An initial C<{> at the beginning of a format argument line was always
+interpreted as the beginning of a block prior to v5.18. In Perl v5.18, it
+started being treated as an ambiguous token. The parser would guess
+whether it was supposed to be an anonymous hash constructor or a block
+based on the contents. Now the previous behavious has been restored.
+[perl #119973]
+
=back
=head1 Known Problems