Install LineageOS on
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Basic requirements

1. Read through the instructions at least once before actually following them, so as to avoid any problems due to any missed steps!
2. Make sure your computer has adb and fastboot. Setup instructions can be found here.
3. Enable USB debugging on your device.
4. Boot your device with the stock OS at least once and check every functionality.
5. LineageOS is provided as-is with no warranty. While we attempt to verify everything works you are installing this at your own risk!

Unlocking the bootloader

These instructions will only work on devices that have not yet been updated past the February 2021 OTA.

You can check this in the Settings application under the “System”, “About” tab, labeled “Security Patch Level”.

If your device was updated past this build, it is not vulnerable to the unlock exploit utilized below, and you cannot run LineageOS on that device.

Downgrading to older builds is not a viable option.

If your device is on the February 2021 OTA, or a build that preceeds it, you can proceed.

1. Unplug the device from your PC.
2. Run sudo apt install libusb-dev and enter your sudo password.
3. Run git clone https://github.com/oddsolutions/sabrina-unlock && cd sabrina-unlock.
4. Hold the button located on the rear of the device’s case, and plug the device into your PC via USB-C. The host should see a new USB device connection in dmesg like this one:

   [10504.840173] usb 1-4.3.1: new high-speed USB device number 16 using xhci_hcd
   [10504.979469] usb 1-4.3.1: New USB device found, idVendor=1b8e, idProduct=c003, bcdDevice= 0.20
   [10504.979495] usb 1-4.3.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
   [10504.979514] usb 1-4.3.1: Product: GX-CHIP
   [10504.979525] usb 1-4.3.1: Manufacturer: Amlogic
   

5. Release the button once the device has been detected by host computer.
6. Run sudo ./unlock.sh and enter your sudo password when asked.
7. Follow the instructions unlock.sh presents you with.
8. Once fastbootd reports “Unlocked”, you may proceed.

Unlocking the bootloader

1. Enable OEM unlock in the Developer options under device Settings, if present.

2. Connect the device to your PC via USB.
3. On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:

   adb -d reboot bootloader
   

   You can also boot into fastboot mode via a key combination:

   • Run adb reboot bootloader.
4. Once the device is in fastboot mode, verify your PC finds it by typing:

   fastboot devices
   

   If you don’t get any output or an error:

   • on Windows: make sure the device appears in the device manager without a triangle. Try other drivers until the command above works!
   • on Linux or macOS: If you see no permissions fastboot try running fastboot as root. When the output is empty, check your USB cable and port!

5. Now type the following command to unlock the bootloader:

   fastboot flashing unlock
   

   info_outline

   Note: At this point the device may display on-screen prompts which will require interaction to continue the process of unlocking the bootloader. Please take whatever actions the device asks you to to proceed.
6. If the device doesn’t automatically reboot, reboot it. It should now be unlocked.
7. Since the device resets completely, you will need to re-enable USB debugging to continue.

Installing Lineage Recovery using fastboot

1. Download Lineage Recovery. Simply download the latest recovery file, named recovery.img.
   warning

   Important: Other recoveries may not work for installation or updates. We strongly recommend to use the one linked above!
2. Connect your device to your PC via USB if it isn’t already.
3. If your device isn’t already in fastboot mode, on the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:

   adb -d reboot bootloader
   

   You can also boot into fastboot mode via a key combination:

   • Run adb reboot bootloader.
4. Once the device is in fastboot mode, verify your PC finds it by typing:

   fastboot devices
   

   If you don’t get any output or an error:

   • on Windows: make sure the device appears in the device manager without a triangle. Try other drivers until the command above works!
   • on Linux or macOS: If you see no permissions fastboot try running fastboot as root. When the output is empty, check your USB cable (preferably use a USB Type-A 2.0 one or a USB hub) and port!
   check

   Tip: Some devices have buggy USB support while in bootloader mode, if you see fastboot hanging with no output when using commands such as fastboot getvar ..., fastboot boot ..., fastboot flash ... you may want to try a different USB port (preferably a USB Type-A 2.0 one) or a USB hub.
5. Flash recovery onto your device:

   fastboot flash recovery recovery.img
   

6. Now reboot into recovery to verify the installation. Do not reboot into the existing OS, since it will overwrite the recovery you just installed!

   • Run adb reboot recovery.

     info_outline

     Note: If you can’t power down the device, try long-pressing the key-combination (if any was used in the instructions above) until the device reboots and follow the instructions above
   info_outline

   Note: If your recovery does not show the LineageOS logo , you accidentally booted into the wrong recovery. Please start at the top of this section!

Installing LineageOS from recovery

1. Download the LineageOS zip file that you would like to install or build the package yourself.
2. If you are not in recovery, reboot into recovery:
   • Run adb reboot recovery.
3. Now tap Factory Reset, then Format data / factory reset and continue with the formatting process. This will remove encryption and delete all files stored in the internal storage, as well as format your cache partition (if you have one).
4. Return to the main menu.
5. Sideload the LineageOS .zip package but do not reboot before you read/followed the rest of the instructions!
   • On the device, select “Apply Update”, then “Apply from ADB” to begin sideload.
   • On the host machine, sideload the package using: adb -d sideload filename.zip.
     check

     Tip: Normally, adb will report Total xfer: 1.00x, but in some cases, even if the process succeeds the output will stop at 47% and report adb: failed to read command: Success. In some cases it will report adb: failed to read command: No error or adb: failed to read command: Undefined error: 0 which is also fine.

Installing Add-Ons

1. Click Apply Update, then Apply from ADB, then adb -d sideload filename.zip for all desired packages in sequence.
   When presented with a screen that says Signature verification failed, click Continue. It is expected as add-ons aren’t signed with LineageOS’s official key!

All set!

Once you have installed everything successfully, you can now reboot your device into the OS for the first time!

• Click the back arrow in the top left of the screen, then “Reboot system now”.