It’s a bit unfortunate to post this in the 4.0 thread, but Whisperfish is currently unable to register a new account on SailfishOS 4.0, due to [4.0.1.45] Regression in rendering of reCAPTCHA in sailfish-components-webview
So if you still haven’t updated to 4.0, please do register first on your 3.4 and then do the upgrade :’-)