By default, Ubuntu Desktop is configured with very strict power management and security settings. If you step away from your keyboard to grab a cup of coffee, you will likely return to find your screen completely black. Upon wiggling the mouse, you are greeted by the lock screen, forcing you to type your long user password just to get back to your open applications.
This automatic screen blanking and locking usually triggers after just 5 minutes of inactivity. While this is excellent security for a laptop used in a busy office, it is incredibly annoying for a desktop PC sitting securely in your own home. You can completely disable the automatic lock screen timeout.
How to Disable the Automatic Screen Lock in Ubuntu
You can adjust the screen blanking and locking timeouts directly from the main GNOME Settings application.
- Click the network/battery icon cluster in the top-right corner of the Ubuntu top bar and select Settings (the gear icon).
- In the left-hand navigation sidebar, scroll down and click on Privacy (or Privacy & Security depending on your exact Ubuntu version).
- In the main window on the right, click on Screen Lock.
- A new dialogue box will appear. Look for the toggle switch labelled Automatic Screen Lock.
- Click the toggle switch to turn it Off.
- To prevent the monitor from turning off entirely, go back to the main left-hand sidebar and click on Power.
- Look for the setting labelled Blank Screen (under the Power Saving Options section).
- Click the drop-down menu and change the setting to Never.
Your Ubuntu PC will now remain fully awake, with the screen brightly illuminated and unlocked, no matter how long you leave it unattended. When you do want to lock your PC for security, simply press Super (Windows Key) + L on your keyboard.