The onDragStart and onDragEnd events do not have parameter descriptions in the docs

[RomanTsukanov]

The event parameters are described in the DragStartEndEvent interface. However, these description do not get to the docs:

https://surveyjs.io/survey-creator/documentation/api-reference/survey-creator#onDragStart
https://surveyjs.io/survey-creator/documentation/api-reference/survey-creator#onDragEnd

Most likely, it's because the events are declared without using this.addCreatorEvent. And this.addCreatorEvent isn't used because the sender parameter is not SurveyCreatorModel:

https://github.com/surveyjs/survey-creator/blob/master/packages/survey-creator-core/src/creator-base.ts#L1747

[RomanTsukanov]

Fixed by #5528