Redeem Steam key to account with Steam OpenID like Humble Bundle

Humble Bundle has started requiring the user to sign in through Steam's OpenID authentication where it then redeems the Steam key on the user's account. I was unable to find any documentation on this

Does Humble Bundle give Steam keys & how to redeem them

Linking your Steam and Humble Bundle Accounts – Humble Bundle

Steam (service), Ultimate Pop Culture Wiki

How to Buy a Humble Bundle and Redeem It on Steam

Humble Bundle now tying Steam account - no Steam keys - Humble

Steam (service) - Wikipedia

I was previously trade banned on Steam. I made another account

How to Redeem a Gifted Bundle or Game – Humble Bundle

Steam (service) - Wikipedia

I randomly got this message today for a game I got in a Humble

What are Steam CD Keys? – PC Games for Steam

Does Humble Bundle give Steam keys & how to redeem them

Free Game Redemption Instructions – Humble Bundle

How to Buy a Humble Bundle and Redeem It on Steam

How to Buy a Humble Bundle and Redeem It on Steam