I updated a few minutes ago and I had the same issue. My setup has a redirect to https:// for the wp-login and I noticed that the loginform action points to https://mysite.url
Looking through the source code I solved the issue with an easy hack. In file wp-login.php line 447 change from:
<form name="loginform" id="loginform" action="<?php echo site_url('wp-login.php', 'login_post') ?>" method="post">
to:
<form name="loginform" id="loginform" action="wp-login.php" method="post">
That’s all. Now I can login as always ??
