I really like Sidebar Login (and it will be great when this other 2.3 bug is fixed).
Please make the error messages customizable in the admin settings. In particular:
<strong>ERROR</strong>: Please enter a username.
<strong>ERROR</strong>: Please enter your password.
(My intent is to remove the
<strong>ERROR</strong>: part, because proper styling makes it clear there is an error.)
Many thanks for the great plugin.