>And to enter it, you ... append it to your password?
Are you implying this is wrong somehow? It's a fairly common way to do 2FA and there's nothing wrong with it. On the backend, all it's doing is taking the input, substringing the final 6 characters and inputting that as the code, and then uses the remaining characters as the password input. It's essentially just a shortcut that allows you to log in with one click rather than having to enter your password, click submit, enter a code, then click submit again.
Per the FAQ, if you for some reason don't want to append it to your password, it'll send you to a normal "Enter your 2FA code" form like you're probably used to.
The main issue for me is that the 2FA is locked to using the Symantec VIP 2FA app, which is disappointing from a usability standpoint.