TYPO3 Core

Since TYPO3 CMS 7.6.5, nested IRRE relations are no longer working. Adding a relation results in an Error 500:

Core: Exception handler (WEB): Uncaught TYPO3 Exception: #1446996136: DOM Object ID data-43-tx_courses_domain_model_course-5-contents-tt_content-95-pi_flexform:data:options:lDEF:content:vDEF-tt_content does not contain required information to extract inline field configuration. | UnexpectedValueException thrown in file /Users/danielkestler/Sites/thnuernberg-typo3/typo3_src-7.6.5/typo3/sysext/backend/Classes/Controller/FormInlineAjaxController.php in line 891. Requested URL: http://thnuernberg.local/typo3/index.php?ajaxID=%2Fajax%2Frecord%2Finline%2Fcreate&ajaxToken=440c24ae45817a10424fefd97ddf2c6311343657

I already tracked the error down to the now missing $newRecord-variable and -handling. If I reinsert it / rollback the changes from the following commit, everythings working as expected: https://review.typo3.org/#/c/47034/2/typo3/sysext/backend/Classes/Controller/FormInlineAjaxController.php