For reference, I have an OG Pixel. Bootloader is unlocked, but everything else is stock Android after flashing the March image just this morning.

To install TWRP, however, you do need an unlocked bootloader first, which is why this particular unofficial version of TWRP for the Galaxy S8 Snapdragon models is rather significant.

Unlocking the bootloader and rooting your Galaxy Nexus is really only half the battle. There may come a time when you need need to lock everything back up, including that bootloader. Thanks to the ...

Android Headlines / Google News / Google Pixel / Version 1.4 of BootUnlocker Will Lock and Unlock the Nexus 5's Bootloader Without Losing Your Data ...