OP
honestone33
Guest
Here is what I did last year when Mojave was released, and what I'll also do when I start testing Catalina:
1. As I always do, made my SuperDuper! backups for each of my Macs to my two external SSDs, which at that time was my clean High Sierra system.
2. Installed the .2 version of Mojave on another external SSD, formatted as APFS.
3. Migrated/copied needed files, folders, settings, etc. from my internal (High Sierra) SSD to that Mojave external SSD. Most of the applications that I needed to upgrade for Mojave compatibility could still be used with High Sierra, but for some of them, I made the necessary adjustments/installations on that Mojave SSD. One of my critical applications, Tech Tool Pro, was not yet compatible with Mojave, so I deleted it from the Mojave SSD after the migration.
With that, I still had my High Sierra system in tact (along with the SuperDuper! backups), along with a separate environment for testing Mojave. All of that worked well.
1. As I always do, made my SuperDuper! backups for each of my Macs to my two external SSDs, which at that time was my clean High Sierra system.
2. Installed the .2 version of Mojave on another external SSD, formatted as APFS.
3. Migrated/copied needed files, folders, settings, etc. from my internal (High Sierra) SSD to that Mojave external SSD. Most of the applications that I needed to upgrade for Mojave compatibility could still be used with High Sierra, but for some of them, I made the necessary adjustments/installations on that Mojave SSD. One of my critical applications, Tech Tool Pro, was not yet compatible with Mojave, so I deleted it from the Mojave SSD after the migration.
With that, I still had my High Sierra system in tact (along with the SuperDuper! backups), along with a separate environment for testing Mojave. All of that worked well.
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