Extract this tar.gz into /var/www/html/roundcube, so you have access to:
<pre>/var/www/html/roundcube/direct_login/index.php

#run
chown -R webapps:webapps direct_login
chmod 700 direct_login/tokens</pre>
<br><br>
Credit to <a href='https://github.com/alexjeen/Roundcube-AutoLogin'>axlejeen / Roundcube-AutoLogin @github</a>