[BUG] Translation of custom TCA fields does not work

[SZChimp]

Describe the bug
When setting l10n_mode to prefixLangTitle can translating a custom fluid content element in the backend, the fields are not translated correctly, but contain the values of the source language.

To Reproduce

1. Create a custom fluid content element (here: single-keyfact) with a custom TCA field (here: subheader) using this configuration:

'subheader' => [
                'label' => $lll . 'text',
                'l10n_mode' => 'prefixLangTitle',
                'config' => [
                    'type' => 'input',
                    'max' => 100,
                    'size' => 100
                ],
            ],

2. Create a content element with type of the fluid content element created in step 1.
3. Enter a value in e.g. german to the field to be translated. Save the content element.
4. In Page module, translate the content element using the "Translate" button, choose the deepl method and translate it.
5. The translated record contains the source language value in its original state.

Expected behavior
Using the translation button in the backend for custom content elements as well as inline relation elements inside those content elements should translate the field values correctly.

Screenshots

TYPO3 Setup

• TYPO3 Version=11.5.36
• Server=Apache
• Database type and version=MySQL 10.4.32-MariaDB-1:10.4.32+maria~ubu2004-log
• PHP version=8.0.30
• DeepL Pro (paid) API
• composer setup

Additional context
I also tried setting the l10n_mode using overrides with
$GLOBALS['TCA']['tt_content']['types']['single-keyfact']['columnsOverrides']['subheader']['l10n_mode'] = 'prefixLangTitle';
or
$GLOBALS['TCA']['tx_typo3szassets_domain_model_keyfact']['columns']['subheader']['l10n_mode'] = 'prefixLangTitle';
or
$GLOBALS['TCA']['tt_content']['types']['single-keyfact']['columns']['subheader']['l10n_mode'] = 'prefixLangTitle';

[SZChimp]

Related to these issues, I think:
#293 #184 #115

[calien666]

Thank you for reporting.
What definition is set inside

$GLOBALS['TCA']['tt_content']['columns']['subheader']['l10n_mode']

I'm not sure, if TYPO3 respects this setting, if overwritten in columnsOverrides.

[SZChimp]

Thank you for reporting. What definition is set inside

$GLOBALS['TCA']['tt_content']['columns']['subheader']['l10n_mode']

I'm not sure, if TYPO3 respects this setting, if overwritten in columnsOverrides.

It is set to prefixLangTitle in Configuration backend module.

[SZChimp]

Do you have an update on this issue?

[Lagerregal42]

(+ 1)
Same problem on several projects and elements :/
And #115 isn't working for those nested elements...

[calien666]

Hi. Could you apply your TCA setup on the fields related to config loaded in backend?

[Lagerregal42]

Hi, thx for the fast reply.

New field in tt_content:

'phases' => [
    'exclude' => 1,
    'label' => 'Phases',
    'config' => [
        'type' => 'inline',
        'foreign_table' => 'tx_XXX_domain_model_phases',
        'foreign_label' => 'title',
        'foreign_field' => 'parent',
        'appearance' => [
            'useSortable' => true,
            'collapseAll' => true,
            'expandSingle' => true,
            'showPossibleLocalizationRecords' => true,
        ],
        'maxitems' => 99,
    ],
],

and in tx_XXX_domain_model_phases.php:

'description' => [
    'label' => 'Description',
    'l10n_mode' => 'prefixLangTitle', // doesn't work with or without this line
    'config' => [
        'enableRichtext' => true,
        'eval' => 'required',
        'type' => 'text',
    ],
],

Setup:

• TYPO3 Version=11.5.39
• Server=nginx/1.26.2
• Database=MySQL 8.0.39
• PHP version=8.1.29
• DeepL Free API
• composer setup

I hope that helps :) If you are missing an information, just let me know.

[calien666]

After talking to @NarkNiro the bug is known and we work on a fix.