When I go to https://www.faforever.com/account/link, and click on the Sign in through STEAM button (below):
I am redirected to https://www.faforever.com/account/connect, and I receive the error:
Error! Your steam account was not successfully linked! Please verify you logged into the website correctly.
This happened after I attempted to link my Steam account while forgetting that I had not set my game library to public. I am now unable to connect my account to a steam account.