Problems after today's upgrade

Since applying today’s update (10 July 2020) to Version 8.0.2891 (2de6ccf), my Contacts shows empty. If I create a new message the contacts are there when I click on the any of the ‘To’ fields, but I can’t see them when I select Contacts. How can I retrieve them?

I also don’t like the more ‘spread out’ appearance of the Messages’ display. How can I remove the spaces between each messages so it looks like the earlier version?