Roundcube adds / before @ sign and imap login fails

[k3on]

I installed Roundcube 1.6 on Ubuntu 20.4.
When I try to log in from Roundcube it fails to auth, in the mail log I am seeing user=info\@domain.com which should be user=info@domain.com
Why Roundcube is adding "\" before @ sign in the username? How can it fix it?

Any help will be appreciated.

Note: I also installed SquirrelMail, it successfully logins with user info@domain.com

[JohnDoh]

That is not something Roundcube usually does. Did you install from source or a package? Do you have any plugins enabled in Roundcube? Have you set username_domain in your config?

Might also be worth enabling imap_debug just to confirm the conversation with the IMAP server.