How do I disable the auto-mounting of internal drives in Ubuntu or Kubuntu 18.04
Solution 1:
The Auto-mounting of disks in Debian-based Linux distros (and perhaps others) comes from a service called udisks2.
Disabling this service will prevent any disk from automatically being mounted, while still allowing manual mounting.
Disable the service - No automatic or manual starts
systemctl mask udisks2
Unmask the service - Will need to either manually run it or restart the computer
systemctl unmask udisks2
systemctl unmask udisks2.service
Stop the service temporarily - This will not persist across restarts
systemctl stop udisks2.service
Get the status
systemctl status udisks2
Credit to @maxschlepzig for answering a similar question about OpenSUSE.