I never knew this. Thanks dude, it seems to be legit when you browse it.
Yeah it's the official forum account. It's normally used just to report security breaches and ddos attacks to the community.
It seems theymos is very busy and have no time to use it anymore. The last post was August 30, 2018 almost 2years and more already.
Having a social active account can be useful since its more way easy yo udpate forum users if there something new or announcement but the text character is limited compared here. Hope theymos used it again, some users here are definitely more active in social than here.