Create sandbox with earlier OS?

[neilio]

Hey, Dave -

Is it craziness to try and somehow set up a sandbox that's running an earlier version of the OS than the main volume after the main volume has been upgraded to the newer version?

I recognize SD wasn't really set up for this situation but wanted to know if you've any experience. I have 10.14 running on the main volume, and want to set up a second volume running from an earlier 10.13 backup I have, but that still uses the Users directory from the main volume.

Thanks! Hope all is well.

[dnanian]

I really wouldn't do that: any shared files may be in a different format under the new major OS version, and as such will probably not work, or potentially lose data...