Make it possible to configure fieldControls for TCA / Flexform select with renderType=selectCheckBox
For a "select" type there are several renderTypes.
For the renderType=selectMultipleSideBySide, you can add additional fieldControls, for the renderType=selectCheckBox you cannot. (The fieldControl is missing in the documentation and also it does not get displayed if you try it in a FlexForm, for the selectMultipleSideBySide is does work however). You also cannot modify the default fieldControl (as far as I know).
The renderType=selectCheckBox already has a default fieldControl "ResetSelection", maybe this is the reason, it is not possible.
I currently have a usecase where it would be very useful to add additional fieldControls for this type (in a Flexform).
I think it might also be useful to be able to add fieldControls for other types.