Fired every time any operation is applied on the model
using applyOperation.
Note that this event is suitable only for very specific use-cases. Use it if you need to listen to every single operation applied on the document. However, in most cases event-change should be used.
A few callbacks are already added to this event by engine internal classes:
highest priority operation is validated,normal priority operation is executed,low priority the ModelDocument updates its version,low priority ModelLivePosition and ModelLiveRange
update themselves.