How To Stop Installing Updates Automatically On Ubuntu Or Debian (Unattended Upgrades)

Debian and Ubuntu based Linux distributions can automatically install the latest security (and others) updates with the use of a package named unattended-upgrades. This unattended-upgrades package is installed by default on Ubuntu (but not on Linux Mint for example) and Debian 9+ with Gnome, and while it’s a nice feature to have, quite a few users complain about it and the Microsoft Windows-like behavior of installing updates with no input from the user. Especially when you want to shutdown or reboot your system while in a hurry.