Apparently, Marriott's "Internet Customer Care" thinks everything is fine. Below is my email to them and their reply.
I am having several problems with the website.
1. When I click on Overview, I get a "General Error" page.
2. When I click to download a bill, the Activity page reloads and no bill is downloaded.
3. When I click on View/Modify or Cancel for a reservation on the MyTrips page, I get a "An unexpected error has occurred" page.
#1 has been going on for a few weeks. #2 and #3 have been going on since the new website was launched.
I am able to do everything I need to using the Marriott App, but it would be nice if the website worked. I know #2 and #3 are common to many users. But I haven't heard of anyone else with problem #1, so I thought I'd let you know.
Hello [my name],
Thank you for reaching out and I hope you are well.
As of today our website is operating properly. Using a different web browser may resolve this issue.
Feel free to let me know if I can help you further.
Marriott Customer Care