The Network Connections feature in the Firewall will be back in the future.
In the meantime if it's important for you, you can retrieve an older version which didn't have the re-worked Firewall (I believe v20.1) from a File Sharing website. It must be an offline version and you would need to disable internet connectivity while installing it. Then once installed, you would have to Set the Program Setting update from Automatic to Manual and then re-enable your internet.