Starting today, two factor authentication for your Twitch account is necessary when creating a new Extension. 2FA is already a requirement when onboarding as an Extension developer, so this should affect only a small set of developers; specifically anyone who has disabled 2FA after the onboarding process.
Developers in the above state will see a button with “Enable 2FA” instead of “+ Create Extensions” to direct them to account settings to turn on this security feature.
Should you have any questions about this change, please add a comment below.