Yes, fixed.  Thank you.

@ SA Admin Kushai Mehrota

There is a fuller description of (apparently) the same problem here:

https://feedback.seekingalpha.com/en/communities/1/topics/192858-front-page-error-message-when-signed-in

This problem recently began affecting me as well.  Verified on Chrome, Brave, and IE.  Windows desktop.  Happens every time.  Pushing plus button or just hitting enter results in no reaction at all when trying to add stocks to a portfolio.