Second monitor stopped working after upgrade

[henrique]

Second monitor stopped working after 11/02/2021 upgrades.

These here:

Start-Date: 2021-11-02 22:59:08
Commandline: apt-get upgrade
Requested-By: henrique (1000)
Upgrade: gnome-shell-extension-desktop-icons:amd64 (20.04.0-3~ubuntu20.04.3, 20.04.0-3~ubuntu20.04.4), ubuntu-advantage-tools:amd64 (27.2.2~20.04.1 , 27.3~20.04.1), linux-firmware:amd64 (1.187.19, 1.187.20)
End-Date: 2021-11-02 23:03:55

Does anyone know how to get it back up and running?

My computer has dual boot, I went to windows and the second monitor works, it just doesn't work in KDE and the problem started after these above mentioned upgrades.

[Snowhog]

First, Welcome!

Using 'upgrade' (apt-get upgrade) is not the 'recommended' approach to keeping your system upgraded. Use: sudo apt update && sudo apt full-upgrade. For edification, see: man apt

Run the commands (sudo apt update && sudo apt full-upgrade) logout and reboot. If the problem persists, report back.

[henrique]

Thank you so much for the welcome, Snowhog!

How nice to know that, I didn't know that "apt-get upgrade" is not recommended, thanks for the tip.

Well, I did what you asked me to do, but unfortunately it still doesn't work.

Is there any way to revert the updates I made yesterday with apt-get upgrade?

[Teunis]

Before reverting something I'd first have a look in the Systems Settings / Screen and monitor.

Btw, what type of video card do you run?
If nVidea you might get some help via the nVidea Server Settings.