Since the launch of the KeeVault service, the Kee extension has stopped offering to save passwords for those not using the KeeVault service. In the past the extension would offer to save new passwords to the local Keepass DB through the RPC plugin. We’d like to see this feature return as many of us still have no interest in the KeeVault service and refuse to allow it to be used in our organizations (as it defaults the enter purpose of using Keepass to have locally controlled databases).
Please check the troubleshooting guide to find out what your problem is. Saving passwords still works for everyone else and this has nothing to do with Kee Vault.