[TYPO3-english] Localization: always use translation parent's value?

[Urs Braem]

To get rid of extbase translation problems, `mergeIfNotBlank` was removed.

Now there is the `localizationStateSelector`. https://docs.typo3.org/typo3cms/TCAReference/ColumnsConfig/Type/Input.html#columns-input-properties-fieldwizard-localizationstateselector

But I only need "Value of default language", without option for "custom". Just use the l10n parent's value for all translations. Is there still an option for that?

As an alternative, 'm thinking about hiding the checkboxes in the localizationStateSelector with css. What do you think about that?