Terminal…
sudo apt install synaptic
sudo apt install unxz
sudo apt install nautilus-admin
nautilus -q
Open Application…
Synaptic Package Manager> Search> Android
Tick: adb and fastboot
Click Apply
Download GSI of your choice.
Terminal…
cd Downloads
unxz gsi-of-your-choice.img.xz
Open Files…
Downloads
Now, open New Window and choose Other Locations> Computer
Right-click on usr, click on Open as Administrator, type in your password
Click to lib/android-sdk/platform-tools
Move gsi-of-your-choice.img from Downloads to platform-tools
Terminal…
cd /usr/lib/android-sdk/platform-tools
adb devices
adb reboot-bootloader
fastboot flashing unlock
Phone…
- Press and hold power button until power off.
- Hold volume up + power until a menu appears on your phone.
- Press volume up until the arrow points to recovery mode.
- Press volume down to select. You should enter recovery mode in few seconds.
- Press volume down until “Enter fastboot” is highlighted.
- Press power to select and enter fastboot.
Terminal…
fastboot flash system gsi-of-your-choice.img
fastboot -w
Phone…
Press reboot system now.
You should now boot into your GSI… be patient.