The widget feature dedicated for displaying a caption under the widget.
This type serves solely as a mixin, and should be added using
the CKEDITOR.plugins.imagebase.addFeature method.
This API is not yet in the final shape, thus it is marked as private. It can change at any point in the future.
_refreshCaption( sender )
Method used to decide if the caption should be displayed for the focused widget and whether it
should contain the placeholder text.
The element that this function should be called on.
Show private items