CSFR-prevention is already implemented but adding this doesn't hurt.
A brief introduction to Same-Site cookies (and the difference between strict and
lax) can be found at
https://blog.mozilla.org/security/2018/04/24/same-site-cookies-in-firefox-60/
TLDR: We use lax since we want the cookies to be sent when the user navigates
safely from an external site.
Cecylia Bocovich