Inline record for NEW tt_content element becomes sys_language_uid=-1
By creating a new tt_content element with included inline records, is not possible for FormInlineAjaxController to determine the current parent (tt_content-element) language. Therefore become all included inline records -1 as sys_language_uid.
For the previously saved tt_content elements woks the patch from Daniel Maier (https://review.typo3.org/#/c/53206/).
My recommendation is to adapt the DOM Object ID for InlineStackProcessor:
- Include the current parent language in the AJAX call and determine the right localizationMode in TcaInlineConfiguration::initializeLocalizationMode for this case not from $result['defaultLanguageRow'], but from this prepared parent language field (probably set in $formDataCompilerInputForParent).
- Extend the patch mentioned above: get the language directly from InlineStack (parent) data instead of DB record.
This issue is based on TYPO3 version 7.6.20. Not verified for other versions.