Trying to downgrade to High Sierra but Time Machine restore upgrades back to Mojave I've been having major issues with Mojave - slow-downs, connectivity issues, crashing - you name it. I tried to downgrade back to High Sierra.  

High Sierra gets installed fresh, but my Time Machine backup was made on Mojave.  

When I hit restore, all the sudden I have Mojave again.  NO!

Is there a way to have my files back without MacOS automatically upgrading me back to Mojave?
You can only do a file restore, individual files/folders rather than a full disk restore.

Once Time Machine has been used on a newer OS, it will not allow you to go back.

Related - Revert to El Capitan
&amp; also covered briefly in How can I download an older version of OS X/macOS?