TYPO3 Core

I think I am very confused by how these two TCA settings regarding localization handling of relations are handled.
I used localizeReferencesAtParentLocalization and wondered why my inline-relations aren't affected at all and not been localized when localizing my parent record. It seems that this setting isn't been used for inline relations and it is not mentioned for inline type fields in the documentation. But the setting is there, handling select-fields and their relations. The documentation however mentiones that this setting is mainly used for inline-relation fields, which is not true.
So either the doc is wrong, or this confusing configuration settings are handled wrong by the code.

https://docs.typo3.org/typo3cms/TCAReference/ColumnsConfig/Type/Select.html#localizereferencesatparentlocalization
https://docs.typo3.org/typo3cms/TCAReference/ColumnsConfig/Type/Inline.html#localizechildrenatparentlocalization

So, this does not work:

        'foreigns' => [
            'label' => 'LLL:EXT:my_ext/Resources/Private/Language/locallang_db.xlf:tx_myext_domain_model_local.foreigns',
            'exclude' => 1,
            'config' => [
                'type' => 'inline',
                'foreign_table' => 'tx_myext_domain_model_foreign',
                'foreign_field' => 'foreign_field',
                'localizeReferencesAtParentLocalization' => TRUE,
                'maxitems' => 9999
            ]
        ],

This does work instead:

        'foreigns' => [
            'label' => 'LLL:EXT:my_ext/Resources/Private/Language/locallang_db.xlf:tx_myext_domain_model_local.foreigns',
            'exclude' => 1,
            'config' => [
                'type' => 'inline',
                'foreign_table' => 'tx_myext_domain_model_foreign',
                'foreign_field' => 'foreign_field',
                'behaviour' => [
                    'localizeChildrenAtParentLocalization' => TRUE
                ],
                'maxitems' => 9999
            ]
        ],