That's on the url without www, check out with https://www.mailrox.com/ and it's safe. (but it will be fixed on the non-www soon).
Just out of curiosity how did you get to the non-www url?
Maybe he did the same as I did. I had logged in, and then simply wanted to go back to front page and figured just removing 'app' of the URL would do the trick.
That is, I did not click any links. :)
Just permanently redirect requests that are missing a prefix to www.mailrox.com. Problem solved.