Installing postmarketOS on the OnePlus 6

This guide shows how to install postmarketOS with GNOME Mobile on the OnePlus 6. Warning: all data on the device will be deleted, so make a backup first.

You can see what to expect after the installation in my video:

Requirements

You need adb and fastboot on your PC. Depending on your distribution:

# Alpine Linux
doas apk add android-tools

# Fedora
sudo dnf install android-tools

# Arch Linux
sudo pacman -S android-tools

# Void Linux
sudo xbps-install -S android-tools

1. Update OxygenOS (both slots)

Enable developer options (About phone, tap the build number 7 times), then turn on USB debugging and OEM unlocking.

Then install via Settings -> System update -> upgrade. Run the upgrade twice so both slots end up on the current version.

2. Unlock the bootloader

Boot into fastboot mode (hold Power and Volume Up), then:

fastboot oem unlock

Confirm on the phone. Skip the Android setup afterwards and boot back into fastboot mode.

3. Erase the DTBO partition

The DTBO partition prevents postmarketOS from booting and has to be removed:

fastboot erase dtbo

4. Flash postmarketOS

Download the images from images.postmarketos.org and extract them:

unxz 20260802-1221-postmarketOS-v26.06-gnome-mobile-4-oneplus-enchilada.img.xz
unxz 20260802-1221-postmarketOS-v26.06-gnome-mobile-4-oneplus-enchilada-boot.img.xz

Then flash them (userdata takes a few minutes):

fastboot flash boot 20260802-1221-postmarketOS-v26.06-gnome-mobile-4-oneplus-enchilada-boot.img
fastboot flash userdata 20260802-1221-postmarketOS-v26.06-gnome-mobile-4-oneplus-enchilada.img
fastboot reboot

5. First boot

The first boot takes longer because the file system is expanded to the full storage size. Login: user / 147147

Change the password and update the system:

passwd
sudo apk upgrade -U