Selection when $state is null

->options([
    '' => 'None',
    '1' => '1x',
    '1.5' => '1.5x',
    '2' => '2x',
    '2.5' => '2.5x',
    '3' => '3x',
])
->formatStateUsing(fn ($state) => $state ?? '')
->dehydrateStateUsing(fn ($state) => $state === '' ? null : $state)

->options([
    null => 'None',
    '1' => '1x',
    '1.5' => '1.5x',
    '2' => '2x',
    '2.5' => '2.5x',
    '3' => '3x',
])