Disable Macbook internal display I own a Macbook Pro 13 2017 (2 thunderbolt ports), and I would like to disable the internal display when an external monitor is connected to it through USB-C.

I have ruled out the following


Turn brightness all the way down in mirrored display mode: Not the best, because the GPU's framebuffer is still doing extra work on that internal display (processing power and battery affected).
Using Clamshell mode: Again, not the best. I only got two USB-C ports, one would be taken by AC power which is a prerequisite for this mode, and another displaying to the external monitor.
Add "niog=1" on NVRAM: Sounds OK, but still a hassle to reset NVRAM every time I want to work on the internal display.


I can think of two solutions


Simulate what is happening to macOS on Clamshell mode without actually closing the lid.
Simulate the Macbook on AC adapter power so I can use Clamshell mode with one USB-C port free.


I would appreciate feedback on this, it would be great to nail this issue.
Why not put a small and not super powerful magnet on the specific area of the sleep wake sensor so that the system thinks the lid is shut?


https://support.apple.com/en-us/HT203315


With power and keyboard connected, you'll have it running in closed-clamshell mode with full benefits for your use case and no need to move the actual display.

There are amazing USB-C pass through docks now - some that sit flush and others with a stand off cable so you can get around the limitation of only having two ports if that's the only sticking point for clamshell mode.


https://www.indiegogo.com/projects/hyperdrive-world-s-1st-usb-c-hub-for-ipad-pro--2#/
https://www.amazon.com/CableDeconn-Thunderbolt-Charging-Multiport-Adapter/dp/B07BK4TRG8/


The good adapters are still in the $50 US range, but the knock off ones are rapidly approaching $10 so you can pick metal or plastic and your warranty / support model of choice if you run out of ports.