Operators in fields logic

I need to make a field required if another field is empty, and I’m doing it with “operators”, as described here, using the following code, but the field empty does not “trigger” the required correctly. Can you tell me how to detect if a field is empty?

$dictionary['Account']['fields']['fiscal_code_c'] = array(
    'name' => 'fiscal_code_c',
    'vname' => 'LBL_FISCAL_CODE',
    'type' => 'varchar',
    'len' => 16,
    'default' => ' ',
    'comment' => 'Codice Fiscale',
    'merge_filter' => 'enabled',
    'logic' => [
        'required' => [
            'key' => 'required',
            'modes' => ['edit', 'create'],
            'params' => [
                'fieldDependencies' => [
                'activeOnFields' => [
                    'vat_number_c' => [
                        ['operator' => 'is-empty']

My problem is that the operator [‘operator’ => ‘is-empty’] doesn’t trigger the empty field. Any suggestion?

Which version of SuiteCRM are you using ?
This is-empty works from v8.4 +

I 'm working on 8.2.4 version. But if i try to enter an arbitrary value, it works instead.

                'activeOnFields' => [
                    'fiscal_code_c' => [

Do you have any workarounds to suggest?

can you try with “is_empty” instead of “is-empty”?

Already did. No way.

If this was all reworked and expanded for v8.4, I would advise trying it with that version. These features are new and they are not used by many, I’m sure there are bugs, at least we know that for v8.4 the devs spent some extra time looking into it…