[No X11 DISPLAY variable was set] UI Test Automation at EC2 with Ubuntu 22.04 LTS

Dear Mike L Thanks for your assistance!

I'm trying to execute provided commands, but I've faced another issue:

ubuntu@ip-172-31-36-14:~$ sudo apt-get install -y ubuntu-desktop
E: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 2496 (unattended-upgr)
N: Be aware that removing the lock file is not a solution and may break your system.
E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
ubuntu@ip-172-31-36-14:~$ sudo apt-get install -y ubuntu-desktop
E: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 2496 (unattended-upgr)
N: Be aware that removing the lock file is not a solution and may break your system.
E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
ubuntu@ip-172-31-36-14:~$ sudo apt-get install  -y gdm3
E: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 2496 (unattended-upgr)
N: Be aware that removing the lock file is not a solution and may break your system.
E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
ubuntu@ip-172-31-36-14:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 22.04.4 LTS
Release:        22.04
Codename:       jammy

1. Is it something that could be fixed?
2. And is it possible to use Ubuntu AMI with already installed GUI?

XRDP uses its own X server. You need to login to graphical desktop, and run your automation job from there.

You can install GNOME directly without PPA

sudo apt-get install -y ubuntu-desktop
sudo apt-get install  -y gdm3

Do ensure that your Ubuntu is using graphical run-level

sudo systemctl set-default graphical.target
sudo systemctl isolate graphical.target

To connect to your graphical console on your Ubuntu 22.04, you may need to install VNC or maybe enable Remote Desktop sharing

Or you can install NICE DCV with console session for graphical console access. Refer to Installing the NICE DCV Server on Linux for installation instructions.

Instead of installing graphical desktop and NICE DCV server manually, you can also use this Ubuntu CloudFormation template to launch a new instance. Do select console for sessionType. Screenshot below for illustration. Refer to this link for guided instructions.