You can manually update your Roundcube installation anytime.
Backup your current installation.
Download a newer version of Roundcube and CAREFULLY read the upgrade instructions contained in the download.
The usual process is to navigate to the bin directory of the new version
Then run the installto.sh script specifying the target directory.
This will copy the new Roundcube files over your existing config and update the database schema of necessary.
Ideally, your customizations are all retained.
By modifying topicdesk installation, you may break compatibility with our future releases. For many, our installer is simply a fast way to get the system online, and they can manage updates from that point forward. Choose your path.