What and Why ?

What is vbmeta?

-> Vbmeta is responsible for checking initial boot to enter into boot or in recovery mode. thats why make sure you flash or restore system with its own vbmeta or you will end up bootloop or stock on fastboot mode.

Why to flash vbmeta meta?

-> Vbmeta is to be flashed when you flash a stock recovery for the first time to retain the recovery and boot into system successfully .

Vbmeta 9 is for cos vendors.
Vbmeta 10 is for rmui vendors.

📍 NOTE :

1. After flashing stock ROM , custom recovery and vbmeta will be replaced by stock .

2. So you will have to flash the respective vbmeta again when u want to flash the custom recovery again.