The picture above was taken by Alexei Watson who states that the new stock recovery in Android L has a few new features. You can now Reboot to Bootloader, and Power down.

First off, the bootloader isn't part of Android, it's what lets the device boot into Android. Device manufacturers generally want you to stick to the version of Android they preloaded on the device.

9. Wait for your boot screen to appear on your phone. Once it does (it’s a big Android with START), type: fastboot oem unlock (Again, it’s ./fastboot oem unlock on a Mac) 10. A bootloader ...

Instructions *Warning – Unlocking the bootloader of your phone, “may” void your warranty. *First things first, you need to setup the Android SDK so that you can use adb and fastboot commands.

If you want to unlock your phone’s bootloader, then you’re in great luck–we have a step-by-step guide on how to unlock the Galaxy Nexus’ bootloader.

As long as your device is bootloader unlocked, that should still work. A device with a locked bootloader will (probably) fail the hash check and won't boot normally.

Google: carriers should give Android users freedom to unlock bootloader An Android security engineer challenges the need for device lockdown and says … ...

How to flash bootloader of your Galaxy Note8 that’s stuck on boot loop By Harvey Hisona November 1, 2019 September 1, 2023 A lot of people encounter boot loop issue from time to time.