I have been made aware of issues with the login on Legacy - it looks like you are logged out, while in reality you are logged in. This only occurs on the homepage, when you click any link, you will be logged in.
If you are not logged in, you will get a warning about an invalid XSRF (Cross Site Request Forgery) token:
This is due to some changes that are being made to Legacy in terms of (possibly) ads as well as improved caching. This however has brought up an issue on the homepage, where you always get a cached version served up, which is not the intention.
This cached version is a non-logged in page and will have an (expired) XSRF token, which causes these issues.
We are currently working on fixing this, I'll let you know as soon as this is fixed.