Nicolas, I sent an email to the help service and this was their reply. It is working for me now…
Thank you for your email. This is appears to be a bug with the Hub which was introduced during a recent update, the bug affects users with a username that contains capital letters.
A bug fix is being looked into, in the meantime you should be able to login with your username in lower case only. You should then be able to access the Hub and it should be working normally.