I compared the new settings with the old settings (on a second computer). The only difference I can see is that in the old version there are separate security settings for SSL and TLS, whereas the new version has SSL/TLS as a single option. Also the old version had just a single check-box for "Use secure authentication", while the new version has a drop-down for "Authentication method".

There is one other thing. The old default port was 995. On the new version the default port is 110. When I change the port to 995 it keeps going back the the 110 default.