Roundcube creates new user with host FQDN instead of localhost

[Taleman]

Debian Stretch, roundcube 1.2.3+dfsg.1-4+deb9u1

Roundcube has created new user_id, with mail_host as FQDN and not localhost as previously. last_login with user where mail_host is localhost was 21. March, last thursday login is mail_host FQDN. I have not knowingly changed anything in a month, except installe ISPConfig 3 Rouncube plugins,  so I do not understand why Roundcube now thinks host is the FQDN, localhost worked since 6th december.

Can I fix this in the database so address books etc of these two users are merged together?

How can I force Roundcube to not do this anymore? I have set
$config['login_lc'] = 2;
to get all lowercase username and domain part, and
$config['default_host'] = 'localhost';
is in both config.inc.php and defaults.inc.php. When log in, I can not see any way to select the mail_host, so it it strange Roundcube does not use localhost anymore.

[JohnDoh]

you should not change the values in defaults.inc.php only put your config vars in config.inc.php

I do not know the ispconfig 3 plugins. do you mean these https://github.com/w2c/ispconfig3_roundcube? a quick look at those shows that the  ispconfig3_autoselect plugin attaches to the authenticate hook and defines the host used for user - that is what gets set in the mail_host field in the database. are you using that one?

[Taleman]

Indeed, this is the set of plugins I installed: https://github.com/w2c/ispconfig3_roundcube

It does look like ispconfig3_autoselect sets the host, and I think this disturturbance appeared after I installed those. Seems it uses what hostname returns as mail host.

Can I somehow force it either way, so mail host is always localhost or always the fqdn that I want? It is going to cause repeated problems if it a coin is tossed depending on what I have or have not installed.

[JohnDoh]

I dont know anything about ispconfig or these plugins. you could try contacting the plugin author for support. but i guess if you don't want what this plugin does then don't use the plugin.

[Taleman]

I do want to use this plugin, so Roundcube users can set vacation message and change password in Roundcube, without going to ISPConfig panel.

It is a surprise the plugins ignore default_host and change to FQDN.

I'll contact the author of the plugins. But to get Roundcube usable now, I suppose I have to change all old users to (user, FQDN) in the database and merge address books together for those that already have both (user, localhost) and (user, FQDN).

Thanks for help.