Hacker News Reader

Yes I just did, in a private window, and all I needed to do was complete a captcha.

But even if your IP is on their naughty list, you can delete that data once you have registered, and I would be very surprised if Proton secretly kept it after you delete it.

> But have you tried to sign up without providing some other email address or a phone number?

Yep.

Here's a video of me doing it: https://streamable.com/8anw1v

If you sign up without another email or phone number you get a warning:

"You did not set a recovery method so account recovery is impossible if you forget your password. Proceed without recovery method?"

...which you can just click through.