NativeSelect Empty item error in 7.6.4

Good Morning,

i just upgraded from 7.6.3 to 7.6.4 and i have a problem with NativeSelect.

I have a select with setNullSelectionAllowed(true); 

start from empty (null) item - ok
select a value - ok
select back empty(null) value - KO, i cannot select back empty item anymore!