+1 to this feature and some way of tracking progress on it, an ETA, that would be great.
I’m facing the same issue - will be implementing a checkbox in my onboarding flow today.
However, as far as I understand GDPR, it’s (near?) impossible to be GDPR-compliant without asking for consent clearly and explicitly before collecting data and tracking that consent. This, in turn, would mean, if I understand the regulations correctly, that it’s impossible (or, perhaps, impractical? there might be solutions I haven’t thought of) to build fully GDPR-compliant authentication with the New Universal Login flow.
Would love to see the option to add that checkbox, hope you can prioritise it. Either way, thank you for your hard work, the New Universal Login is great overall!