chromebook how to backup firmware || restore

1、https://johnlewis.ie/Chromebook-ROMs/utils/flashrom
sudo flashrom –r


2、https://johnlewis.ie/flash_chromebook_rom.sh
option 4


3、
https://raw.githubusercontent.com/MattDevo/scripts/master/firmware.sh

This shell have backup option.

Then

http://mrchromebox.tech/firmware-util.sh   call   firemware.sh

So try fireware.sh


===== flashrom =====

https://johnlewis.ie/Chromebook-ROMs/utils/flashrom


chmod +x flashrom
sudo ./flashrom -w xxxxxbios.bin


==== restore =====
https://docs.google.com/document/d/1Q_5_rTv2CEMgXiAm86IXGOVGBtb8JWXj-zcCPzAEEkQ/edit