Unable to Open a Message in Message Center

Open to My Norton (Version 22.21.10.40), on my Windows 7 PC.  Norton shows me that 1 new message is available.  Double click on the envelope icon that has the little green "1" dot in it.  Message Center window opens but no message appears. 
I suspect it may have to do with my Firefox blocking popups.  I can create an Exception to popup blocking in Firefox by specifying a website. 
Question #1:  can popup blocking affect my ability to view messages in Norton Message Center?
Question #2:  If the answer to Question #1 is YES, please provide the https://   ????     address to use in order to create an Exception in my Firefox popup blocking settings.
Question #3:  If popup blocking is NOT the cause of my inability to view messages in Norton Message Center, please provide other possible problems.   If the answer to Question #3 is too complicated, I will just ignore Norton messages in the future  :)
 

Please review related:
https://community.norton.com/en/forums/how-delete-unread-message-there-no-mesage

https://community.norton.com/en/forums/cant-seeread-norton-email-coming-notification

.... Message Center no message.... may be cosmetic glitch on Win 7