Here is description how does it works. It is open source solution which generate the password by login, site and master password.
It looks like "one password for all sites". Is it right? In general, person have one login for all sites. In this case we have only one unknown input parameter - master password and it is the same for all sites.
If one of my passwords will be stolen, the intruder will be able to restore my master password (from site, login, password and open-source function) and then get my passwords for all the sites.
Am I right ?