Downgrade

[biggie!]

IS IT POSSIBLE TO DOWNGRADE TO CATALINA WITHOUT LOSING YOUR DATA?

 

[Ritsuka]

Copy your data to an external disk, and then copy them back after you initialised the disk and reinstalled the older macOS version.

 

[h9826790]

You can only recovery from backup. There is no direct downgrade route.

 

[telemoxy]

If you backed up before you installed you might be able to return to that backup.