Internal storage

[Exiled Eye]

Does the bootloader unlock (using the official tool) wipe the internal storage?
Does the .bat file installation of xiaomi.eu rom wipe the internal storage?

Asking to know if i have to backup things like photos etc. or i can keep them on the device without loosing them.

 

[JiaiJ]

I believe the unlock wipe the internal storage, but even if it didn't, format data is a requirement when switching between different ROMs. Even going from Stable EU to Weekly EU it is heavily recommended.

Better safe than sorry.