Using FAL in gridelements fails with FATAL
we currently switch to TYPO3 7.6 LTS, but now assigning FAL inline images in the gridelement fails:
#1446996319: Configuration retrieved from FlexForm is incomplete or not of type "inline". (More information) UnexpectedValueException thrown in file /var/www/vhosts/php-sources/typo3_src-7/typo3/sysext/backend/Classes/Controller/FormInlineAjaxController.php in line 811.
The Usecase is:
- Open gridelement
- Click button "Add Image"
- Select image from element brower
- Ajax returns with JS alert "Error: 500 Internal Server Error"
The complete error stack is attached, also the used flexform.