How do I keep my external display on after closing my laptop lid?

Question

Prior to updating to macOS 12.2.1, when I closed my laptop lid, the external display would stay on and I could use my laptop with the lid closed.

After updating to macOS 12.2.1, when I close the lid, the external display goes black and does not come back on.

How do I keep my external display on after closing my laptop lid?

I am running macOS 12.2.1 on a 13-inch, M1, 2020 with LG Ultra HD Display (Model 27BK6U).

Answer 1

I just learned, which port it's plugged into matters.

The port closer to the user will allow the second display to be used with the lid closed, and the further port (closer to the internal display) will not.

Answer 2

If you want to keep the display on after closing your lid without requiring a power adapter (eg for battery health), I've found an app called Fermata that can do just that.

Setup:

• Download the latest release of Fermata from GitHub (as of writing, Fermata-136.zip)
• Unzip, run, move to /Applications
• In Preferences:
  • "Manual activation duration": set to 1 minute
  • "When activated, also prevent": tick "Display Sleep"
  • Tick "Launch Fermata at login"

Usage:

• Click the Fermata tray icon and click "Postpone Lid Close Sleep". Then close the lid within the next 1 minute.

  (Do this every time you want to dock to your external display, just before closing the lid.)

Other approaches:

• Use the script here (this is what Fermata 1.2 uses internally).
• Use the Amphetamine app. This works automatically in the background but I found it too flaky.

I'm testing on a MacBook Pro 14" 2021 (M1) with macOS Monterey 12.6.