Thanks it works indeed!
SSO plugins (like facebook, twitter) choose username without enable username changes
I want to use the SSO plugins for Twitter and Facebook, but I don't like it the plugins pick the real names from Facebook and Twitter for NodeBB forum. I don't want to enable username changes, but I want the users if they use SSO plugins that they can set their username, and not forced to use the real name of facebook/twitter.
People of my forum complained, because they didn't want their full name was their username on my forum.