I wanted to just raise an issue I have encountered.
When using the Show/Hide option in the New UX the list of items does not appear correctly. It looks exactly the same with line items, time or imagine any other dimension you may have in your module.
I am using Opera with 100% zoom. I tested this on my second screen but the issue is still visible on the laptop screen.
It's working fine for me. Can you clear your cache in your existing browser or try another browser? If the problem persists better to log a ticket with Support@anaplan.com