Hello !
New tries this morning : it boots powered up through USB.
I previously used a USB C <-> USB A connector (USB-C connected to a powerful enough charger, USB A in the white USB port of the Vero,), but it does’nt work with this cable.
Using a USB A - USB A cable I previously built for debuging works !
So I guess it’s the power plug which fails ! (ouf, not the Vero itself !)