Bug #90542
Updated by Georg Ringer about 4 years ago
The TCA option invertStateDisplay for checkboxes is not evaluated when used in flexforms. The reason for this is a strict comparison when rendering (see https://forge.typo3.org/projects/typo3cms-core/repository/revisions/master/entry/typo3/sysext/backend/Classes/Form/Element/CheckboxToggleElement.php#L176). Because flexform values are strings, the comparison evaluates to false. true. An easy fix would be to force the invertStateDisplay value to a boolean while sanitizing: https://forge.typo3.org/projects/typo3cms-core/repository/revisions/master/entry/typo3/sysext/backend/Classes/Form/FormDataProvider/TcaCheckboxItems.php#L131