Software Updates Notification missing

In Ubuntu MATE 18.04 how do you get the notifications of pending updates? I mean the shield icon with a question mark when updates are pending, a check mark when the system is up to date and a red X when updates couldn' t be installed correctly.

Thank you in advance.

Hello,
Your request is about Linux Mint. Ubuntu Mate don't have a notification icon for updates pending, or progress. To improve that I make a script:

Outstanding response!

Just a newby concern: the 'sudo apt full-upgrade' command won't upgrade 18.04 LTS to 19.10, will it? I want to stay on the LTS version.

Thank you in advance.

No, you will keep your version. The command which is increase the version is 'do-release-upgrade' and not 'full-upgrade'