Big Sur Clamshell mode

[yoshi]

I was running into the issue of not being able to run clamshell mode in Big Sur. I seemed to have fixed it by running:

sudo pmset -a disablesleep 1

and entering my password.


To stop sleep entirely:
sudo pmset -a disablesleep 1

To revert, allowing sleep again:
sudo pmset -a disablesleep 0

Hope this helps some people