How to Override the Default Behavior - FXMisc/RichTextFX GitHub Wiki

See OverrideBehaviorDemo to know how to override the default behavior and then check out GenericStyledAreaBehavior to see what specifically you need to override. You might also need to override some of the mouse behavior hooks (e.g. onSelectionDrop(Consumer<MouseEvent>) in GenericStyledArea). Some behavior (selecting some text and then dragging it horizontally should scroll the viewport in that direction if there is currently unseen content in that direction) is more complex and harder to override when using just InputMaps from WellBehavedFX. So, one can override them using the mouse behavior hooks.