Field display logic not working on multi select fields

[BastianHammer]

Issue

My goal:
Based on a multi select option, I'd like to show another field.

I've added 4 fields through the studio:

• test1_c (text field)
• test2_c (text field)
• singleselect_c (drop down)
• optionfield_c (multi select)

The drop down and the multi select both use the same list:

• test1
• test2

Then, I add the code:

sudo -u www-data vi extensions/myExtension/modules/Accounts/Service/FieldDefinitions/OptionFieldDisplayLogicMapper.php

<?php

namespace App\Extension\myExtension\modules\Accounts\Service\FieldDefinitions;

use App\FieldDefinitions\Entity\FieldDefinition;
use App\FieldDefinitions\LegacyHandler\FieldDefinitionMapperInterface;

class OptionFieldDisplayLogicMapper implements FieldDefinitionMapperInterface
{
    public function getKey(): string
    {
        return 'optionfield-display-logic-mapper';
    }

    public function getModule(): string
    {
        return 'accounts';
    }

    public function map(FieldDefinition $definition): void
    {
        $vardefs = $definition->getVardef();

        if (isset($vardefs['test1_c'])) {
            $vardefs['test1_c']['displayLogic']['show_only_if_test1_selected'] = [
                'key' => 'displayType',
                'modes' => ['detail', 'edit', 'create'],
                'params' => [
                    'fieldDependencies' => ['optionfield_c'],
                    'targetDisplayType' => 'none',
                    'activeOnFields' => [
                        'optionfield_c' => [
                            ['operator' => 'not-equal', 'values' => ['test1']],
                        ],
                    ],
                ],
            ];
        }

        if (isset($vardefs['test2_c'])) {
            $vardefs['test2_c']['displayLogic']['show_only_if_test2_selected'] = [
                'key' => 'displayType',
                'modes' => ['detail', 'edit', 'create'],
                'params' => [
                    'fieldDependencies' => ['optionfield_c'],
                    'targetDisplayType' => 'none',
                    'activeOnFields' => [
                        'optionfield_c' => [
                            ['operator' => 'not-equal', 'values' => ['test2']],
                        ],
                    ],
                ],
            ];
        }

        $definition->setVardef($vardefs);
    }
}

and clear the cache:

sudo -u www-data /usr/bin/php8.4 bin/console cache:clear

If I replace optionfield_c with singleselect_c in the code, it's working.
I can select the option and the correct field is being displayed (right away, without saving the record).

If I use optionfield_c from the multi select and have nothing selected, it's all good:

If I edit the record and select test 1, nothing happens :( :

(no error in the browser console as well)

After saving the record, both text fields show up :( :

Possible Fix

No response

Steps to Reproduce the Issue

1. See above

Context

No response

Version

8.10.2

What browser are you currently using?

Firefox

Browser Version

No response

Environment Information

MariaDB, PHP 8.4

Operating System and Version

Ubuntu 24