Thanks.
From what you have explained in Something Went Wrong! - #4 by Ego
I understand it should be harmless since it is just about:tor page
seems that when you just have updated your browser this page auto opens and from there the confusion of new users that see it and they are told they are not using tor.
So, it’s just a false positive of the built-in tor test that is not made for whonix. From what I understood.