How to (sort of) restore Classic view in Catalina's Mail v 13.0: https://becomethesolution.com/blogs/mac/fix-restore-classic-view-in-mac-mail-v13-0-macos-catalina-10-15
How to (sort of) restore Classic view in Catalina's Mail v 13.0: https://becomethesolution.com/blogs/mac/fix-restore-classic-view-in-mac-mail-v13-0-macos-catalina-10-15