So #Signal is supposed to be installed on a smartphone before you can use it on desktop? Unofficially, the desktop version is perfectly capable of creating new accounts. All you need is a number to receive an SMS or voice mail. Here is how.
Why is this step necessary? mastodon.technology might not be the server where you are registered, so we need to redirect you to your home server first.
Don't have an account? You can sign up here