Disclaimer: do not follow this tutorial if you cannot afford losing your Pixelbook. I accept no liability for any loss. Posting questions in the subreddit r/chrultrabook is your best chance of getting expert help.
Introduction
My Google Pixelbook expires on June 2024. I have decided I will not replace the hardware, so to replace ChromeOS, I have to reflash the BIOS, format partitions and install Linux. I could do this next year but I actually missed using Linux and GNOME as my daily driver after years with ChromeOS and i3.
I didn’t expect an easy setup but I expect a stable experience once it’s set up. This article describes how I’ve managed to install and use Ubuntu on a Google Pixelbook as it’s sole operating system. Beware, it’s not for the faint of heart.
Preparation
Besides thorough research, I personally didn’t spend too much time preparing, possibly because ChromeOS is very oriented towards using the Google services and the Google Drive, so most of the data should already be located in the cloud.
In any case, I would suggest backing up all your local data to the Google Drive. It should be a matter of dragging and dropping folders in the file manager. Make sure you let the folders sync completely with the cloud otherwise, once the user data is erased, the data will be lost.
Secondly, we need to create a bootable USB stick with a Linux distribution ISO installer. I have chosen Ubuntu Desktop 22.04 LTS for this case. I have used another Linux machine to download the ISO and burn it to the USB stick. Once the ISO was downloaded, I ran the command below to create the bootable USB stick:
dd if=Downloads/ubuntu-22.04.3-desktop-amd64.iso of=/dev/sdb bs=4M status=progress conv=fdatasync
The device to use in the of field - /dev/sdb in my case - should be obvious by running lsblk in the terminal. I used an adapter between USB-A and USB-C to plug the USB stick to the pixelbook. There are many other ways of creating a bootable USB stick. In Windows, Rufus seems to be a popular choice. I’ve read reports selecting the ‘dd image’ mode is important later on.
Now, on to the hard stuff.
Developer mode
Despite of ChromeOS being Linux under the bonnet, the Google Pixelbook is very well locked up and secure. It has proprietary BIOS, firmwares, etc. Therefore, it’s not possible by default to sideload an installer of an alternative operating system and install it side by side or in place of ChromeOS. One has to get access and reflash the ROM with an open BIOS like Coreboot to be able to do so.
I have used the Firmware Utility Script by MrChromebox described in his site to install the firmware. This script must be run in the crosh terminal. The terminal in the crostini container does not have full access to the hardware, so it’s impossible to flash the ROM from there. To get access to the crosh shell, the pixelbook must be in developer mode. One of the side effects of enabling the developer mode is essentially doing a factory reset to the pixelbook, so at this point you should be prepared to erase all local data.
The developer mode is accessed via the recovery menu. To reboot to recovery, press and hold Esc + Refresh and then press the power button. Once you see the recovery menu, you can let go of Esc + Refresh, as described here in step 3. To enable developer mode, press Ctrl + D and confirm, as described here.
The next time the pixelbook is started, it will show a welcome screen like it’s being switched on for the first time. I believe the crosh terminal can be invoked from the first screen with a Ctrl + Alt + T. Otherwise, you’ll have to configure an account, login normally and finally invoke crosh using the same combination from there.
Removing write protection and flashing BIOS
Unfortunately, we can’t just run the script and flash the ROM, as the ROM is write-protected at hardware-level. To disable the write protection, we have to simply disconnect the battery, a process that involves removing the back panel - where the battery is glued on - and disconnecting a flat cable from the motherboard, a process very well described in this iFixit article.
It’s understandable if you don’t feel confident proceeding with this madness. At this point, you can still boot to recovery, disable developer mode and restart normally to ChromeOS. There is another method described in MrChromebox’s website that should be less invasive but requires a special debug USB cable, which I have not tried.
Assuming my readership was brave enough to go ahead with opening the Pixelbook and disconnecting the battery, it is possible now to start the Pixelbook, launch the crosh with Ctrl + Alt + T, type shell, launch the Firmware Utility Script with
cd; curl -LO mrchromebox.tech/firmware-util.sh && sudo bash firmware-util.sh
as described in here, and select Install/Update UEFI (Full ROM) Firmware. This is the last time you’ll see ChromeOS in this pixelbook, before shutting down.
The battery can now be reconnected to the motherboard and the back panel reattached, to enable write-protection again.
Installing Ubuntu and mitigating some quirks
In the next reboot, you’ll be greeted with the Coreboot logo. Chances are that you’ve rebooted with the USB stick plugged in but it is not being detected in the Coreboot boot menu. The solution for me was to go back to the main/root menu, unplug the USB stick, wait a couple of seconds, plug it back again, wait ~3 seconds and check the boot menu again. It didn’t work straight way with me and this could be quite distressing until it works.
Once you’ll see an USB-related entry in the boot menu and select it, things will then become quite familiar if you’ve installed Ubuntu before. In my case, during the whole installation process, the picture was flipped upside down. This shouldn’t prevent completing the installation, if we ignore the awkwardness. In the first boot after the installation the picture was oriented correctly.
By now, you should have everything working except, I think, sound and the top row of the keyboard. I have not tested whether input events from the stylus are being recognised but intend to do so soon. It would be great if the stylus still worked with it for some ad-hoc whiteboarding.
To fix the sound and the keyboard, I have followed this thread in Reddit. The important part entails installing the packages pixelbook-alsa and pixelbook-keybd from this folder in Google Drive. I have not tried the pixelbook-sensors package. Sound and keyboard should now work out of the box.
The only issue I have at the moment is, whenever I plug headphones in or out, the sound device is not switched automatically. It has to be done manually in the Settings > Sound dialogue, which is a bit a annoying. I’ll try to fix this issue once Ubuntu 23.10 comes out.
Other than that, it has been running quite stable so far, GNOME is a very polished experience and, in the age of PWAs and the cloud, I don’t feel limited in any way. It would be great to have more than 8 GB of RAM for more browser tabs.