[BUGFIX] File Picker is not working anymore with 6.2

Change-Id: Id6afae644234fb5b1ddeff7b947e28ff98a9fb01
Releases: 3.0
Resolves: #55878
Reviewed-on: https://review.typo3.org/27545
Reviewed-by: Fabien Udriot
Tested-by: Fabien Udriot