You've got a long export running, you need to plug into a monitor or just tidy the desk, and you close the lid. A few seconds later the fan stops, the progress bar freezes, and the job sits there waiting for you to open the lid again.

Closing the lid is its own sleep trigger, separate from the idle timer. Here's how to control it.

On Windows

Windows lets you decide what the lid does, separately for battery and plugged in.

  • Open the Start menu, type Control Panel, and go to Hardware and Sound > Power Options.
  • Click Choose what closing the lid does.
  • Next to When I close the lid, set Plugged in to Do nothing.
  • Click Save changes.

On recent Windows 11 builds you'll also find lid controls under Settings > System > Power & battery. Leave the battery option set to Sleep. A closed laptop running on battery in a bag is how batteries drain and machines overheat.

On a Mac

Macs sleep when the lid closes, with one built-in exception called clamshell mode. Your Mac keeps running with the lid closed when:

  • it's connected to power,
  • an external display is connected, and
  • an external keyboard or mouse is connected (or one you used before and that's still paired).

Without an external display, a closed MacBook sleeps. There are Terminal commands that change this system-wide, but they stop the Mac sleeping in a closed bag too, which risks heat damage, so we don't recommend them.

What a browser extension can do

Max Mouse Mover runs inside Chrome. It can keep your screen from dimming and sleeping while the lid is open, and it keeps the pages you have open seeing activity. It can't stop a laptop sleeping when the lid closes, because that decision is made by the operating system and the hardware, below anything a browser can touch.

So the reliable setup for a long job is simple: plugged in, lid behavior set to Do nothing (Windows) or an external display connected (Mac), and Max Mouse Mover on to keep the screen and session awake. When you come back, the brief tells you what you missed.

Keep it cool

A laptop working with its lid shut has less room to shed heat. Leave it on a hard, flat surface, not a bed or a sofa, and don't put it in a bag while it's still running.