add the ability to use a Yubikey or other kinds of usb 2auth devices
It would be really nice to use a usb device for 2auth (something like the yubikeys).
Rob Frawley 2nd commented
Right now 2-step-auth on Twitch is such a minimal implementation, only supporting SMS codes (insecure) and Authy integration only. Why can't I at least see a bar-code with my 2-step-auth key so applications outside of Authy can be used, like Google Authenticator. Displaying the 2-step-auth key barcode at setup would even allow the use of OATH-TOTP codes using security keys like the YubiKey 4 and 5.
But ultimately, as has already been described by the many others commenting in this suggestion thread, it is important that full support for security keys is ultimately added. At a minimum you need to support "FIDO U2F/UAF" (https://en.wikipedia.org/wiki/Universal_2nd_Factor), but it would also be beneficial to support the newer "FIDO 2 UAF/U2F, WebAuthn, CTAP" standard (https://fidoalliance.org/fido2/)
The security improvements if this was implemented would be major. 2FA is a good step for most attacks, but U2F is more convenient and secure.
In addition to the benefits of U2F on its own, allowing people to add multiple 2FA options (code generator app + one or more U2F keys) reduces the chance of account lockouts.
Would be really useful for full-time streamers who would suffer significantly from having a compromised account.
I'd higly like to see the possibility of having U2F or at least hardware supported OTP as a possibility of 2FA