https://material-ui.com/api/select/
The docs says that you cannot use empty string value for value field. As long as this is eventually acceptable, there is an issue, because for some reason null value also does not work. These both totally break my communication with backend service, because it seems I'll have to find and replace the values before saving (I do want to save null).
If I change the nulls to any non-empty string, it works, but it isnt a solution.

const options = [{ name: 'Default', value: null }, { name: 'Alternative', value: 'alternative' }]; const currentValue = null;

   <Select
       name={`content.${index}.target`}
                    key={`content.${index}.target`}
                    onChange={handleChange}
                    value={currentValue}>
                    {options.map((option) => <MenuItem value={option.value}>
                        {option.name}
                    </MenuItem>)}
                </Select>