I used Apple Mail for many years, starting in Mountain Lion! As each new version of OS/X came along, everything got updated. Gave me some problems for the series of versions from Mavericks to High Sierra, as each release brought in its own selection of bug-regressions, and wasted many hours after each OS upgrade simply repairing the damage to my message-base inflicted by the upgrade.
I also found I had some serious but mysterious bugs in mail that others did not experience, as well as the well-know ones! In the end I decided I’d had enough, and switched to a succession of other mail clients, none of which have proved adequate for my needs. I now want to go back to Apple Mail!
Because some of the bugs I used to experience seemed to be unique to me, I suspect that my Apple Mail installation has, over the years and over many OS upgrades become corrupt, and so before I start trying to use the app again, I really want to get a clean install. With an app-store app this would be easy - do a full uninstall of the app using CleanMyMac, make sure that all data has gone, and then re-download the app from the App Store. Unfortunately, Mail is considered to be part of MacOS, and cannot be uninstalled, nor installed except as part of an OS installation.
Does anyone know if there is any way to get a fresh Mail installation except as part of a nuke and pave exercise?
Alternatively, is there any way of selectively excluding apps from the migration process after installing a new MacOS version? (I need to upgrade to Mojave, so that might be an opportunity!)