varahash

1. Boot into Recovery mode (by pressing CMD+R while boot macOS)

2. Unmount APFS volumes automaticaly mounted by Recovery (where /dev/disk2 is your APFS container)

    $ diskutil unmountDisk /dev/disk2
    Unmount of all volumes on disk2 was successful
  
3. Unlock APFS volumes (in case FileVault enabled for this volume)

    $ diskutil apfs unlockVolume /dev/disk2s1 -nomount

Aneureka

# Add a scheduled sync task at 4:00 am
# Some privileges should be granted to `cron` *manually*, so you may test `* * * * *` (run every second) first to grant the needed privileges in advance
0 4 * * * osascript /path/to/your/sync-from-chrome-to-safari.scpt