I would claim the only way to make a webapp with login securely function in a usable manner is to use a session cookie with secure transport policy. Do you really need more than that?
See 3.2 in data protection working party recommendations: https://ec.europa.eu/justice/article-29/documentation/opinio...
See 3.2 in data protection working party recommendations: https://ec.europa.eu/justice/article-29/documentation/opinio...