Add "Remember Browser" when logging in via 2FA
Some services will "remember" the browser and only require 2FA when logging in on a browser that's unrecognized. I really like this because it helps balance security with ease of access for regular users. Please consider adding an option to make 2FA just slightly less burdensome for users accessing the account from the same browser, hour after hour, day after day.
Even if I don't use 2FA, please remember my browser login, so next time I comeback I don't have to step through the login process. Facebook is an example. Heroku is another. Many services just set an encrypted browser cookie to remember the login.