Issue with get free deso and public keys

Trying to make the free Deso link work with a public key on https://nftz.me/signup but getting some errors.

What is the idea here? To make the button get free Deso work as a window.open() 

Used some variants of:

`https://identity.deso.org/get-deso?derive=false&derivedPublicKey=BC1YLiqkZMS9jA1k9PtGgaKG3fra84cegjEGg5XY2fiYo1tCupy9rwK`

How should we format that link?


