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Macbook in thumbshell mode


I've decided to rearrange my setup after I got a new 24" monitor from Carousel recently. I make this monitor as a primary monitor, and the laptop's screen as the secondary. Below is my setup with my work macbook and the monitor. Pretty neat.



However, after several days of use, I think a single 24" monitor is enough for me to work. I found myself rarely looking at the secondary monitor. Plus, with the above setup, I've encounter this one specific problem with my browser.

I use Arc (btw). The tab is anchored to the left side of the screen. Usually when I'm on the mac itself, I just hard slam to cursor to the very left of my screen to bring out the Arc tab sidebar.

This is what happen when I'm doing the same with this setup:

In case the video doesn't load, click here.

The behavior is annoying because I need to slow the mouse down so that the sidebar can be shown. So I think what if I can just turn off the laptop display? Since, again, I'm now comfortable working with just the external monitor.

To recap, the goal I wanted to achieve is to:

  • Completely turn off the laptop display.

There are two simple solution. Firstly, just close the Mac screen. It will turn off the primary display just output to external display.

But, the speaker output will be affected. The sound, especially if there is a speech, will not clear enough to hear. I didn't prefer using headphone/earphones for listening, except for video calls. For the record, my monitor have a pair of speakers, but ya know the sound quality will be like.

I still wanted the full experience listening from Mac speaker. So this option is out of the equation.

Secondly, move the Mac to right side of the monitor. So I'm no longer be annoyed from the Arc browser sidebar behavior. But, this doesn't help me achieve the goal I mentioned above. So this one is also out of the equation.

I tried looking for the similar option that laptop Windows conviently have; "External monitor only", but I can't find the equivalance of it on Mac.

Windows Project setting

I also found this hacky trick on Reddit (can't found the original post) that suggest to rearrange the display arrangement so mouse cannot cross the laptop screen.

hacky solution mac rearrange display

It might work. It solved the Arc sidebar behavior. But it still doesn't turn off the display completely. Sometimes, some window launched to the other display, and with this setup, it is difficult to move the window around.

Another trick that I've read is to put magnets to the hall sensor of the Mac so that it thinks the lid is closed. So, I searched for fridge magnets I have and I tried.

mac fridge magnets

Well, it doesn't work. Further searches on the internet, I found that the magnet trick only works on older Macbook.

Quoted from Alin Panaitu's blogpost:

With the new 2021 design, the MacBook has a hinge sensor, that can detect not only if the lid is closed, but also the angle of its closing. Magnets can’t trick’em anymore.

Oh, also, the blogpost above is a good to read. He discussed this same topic but on the software side.

Behold, the thumbshell mode

Lastly, I found this nice blog where he set his Mac in thumbshell mode (Yup, I got the term thumbshell mode from this blogpost). Seems like I have found people that share similar problem with me. His solution is simple, just open the lid like normal, put a finger, and close the lid slowly until it reaches the finger.

The laptop screen display will turn off, leaving the display output to the monitor only. Just like what I needed.

Foliovision's thumbshell mode

So I went to try on my Macbook Air and it works. But then I remember, I have extra keyboard gasket lying around, and I think the height/width is similar to the finder, so why not just put that thing in here.

Keyboard extra gasket

And the I close the lid slowly until it reaches the gasket. It still works, and it is more convinient than using my finger. 😄

Laptop thumbshell 1

Laptop thumbshell 2

What about the pros using this method? I think I agree with what Alec has highlighted in his blogpost, which are:

heat. Even a slender air vent lets a lot more heat out than no air vent. Hence fans come on much later and at a lower RPM.

I didn't notice much difference using my Macbook Air, but I definitely more preferable the letting all the heat accumulated near the display panel.

There are several drawbacks I've noticed. One of which is about sound. Let's quote from Alec's blogpost:

What the thumb clamshell method doesn’t help enough with is are the speakers. The sound still isn’t nearly as good as in open clamshell but on a scale of ten:

open: 9, closed: 2, thumb clamshell: 6

When fully closed, the output from speaker is slower, reduced richness, and the speech isn't very clear. Using thumbshell mode, the sound is a bit better but not as the best when fully open the lid.

I need to take extra care considering the gasket I put in there. When I need to pack my Macbook, I always remember need to take out the gasket first. Also, if you have people around you that might accidentally close the lid, you'l need to take extra cautious.

Thumbshell mode achieved my goal. Here the overall looks of my setup now.

setup with thumbshell

On another note, I think I'm transitioning to the high IQ population by now. Haha jk 😂

monitor iq bell curve meme

See ya!