TYPO3 Core

If you create your own tca field of type=file
the basicoverlayPalette is used also for image,videos and audio files.

This results in, for example, the alternative text field not being displayed by default in palettes for filetypes images when they are created in TCA itself. You have to override the child tca to use the palettes for imageoverlayPalette, audioOverlayPalette, videoOverlayPalette.

These standard filetype palettes should be used directly.
Fluidstyled content elements already do this. The output of specific palette will be aligned to these elements.
Palettes for already set type=file fields are extended automatically and have to be adjusted by the integrators if necessary.