File locations are a bit all over the shop in this version, so this is how it works out. For reference
- the actual program files are downloaded to /usr/share/roundcube/
- the config happens in /etc/roundcube
- the web directory is in /var/lib/roundcube, which contains symlinks to the above locations. This is the one you add to your nginx / apache config.
# Get the plugin and put it in the right place. In this case we're doing Filters plugin
cd /usr/share/roundcube/plugins/
wget https://github.com/6ec123321/filters/archive/master.zip
unzip master.zip
rm master.zip
mv filters-master/ filters
# Symlink the web directory to the plugin you just downloaded.
cd /var/lib/roundcube/plugins/
ln -s /usr/share/roundcube/plugins/filters/
# Edit the config to add the filters plugin.
nano /etc/roundcube/config.inc.php
eg. --->
$config['plugins'] = array(
'password',
'filters',
);