Issue with @@config@@ on custom password reset

I’m trying to get the @@config@@ variable in my custom password reset page. Nevertheless, I’m getting the following error

Uncaught DOMException: Failed to execute 'atob' on 'Window': The string to be decoded is not correctly encoded.
    at <anonymous>:1:46

The code that’s breaking is
var config = JSON.parse(decodeURIComponent(escape(window.atob('@@config@@'))));

I am also facing this issue. Were you able to resolve this issue?