src/vs/workbench/contrib/mergeEditor/browser/view/viewZones.ts/Spacer/create
class Spacer:	override create(
		viewZoneChangeAccessor: IViewZoneChangeAccessor,
		viewZoneIdsToCleanUp: string[],
		disposableStore: DisposableStore
	): void {
		viewZoneIdsToCleanUp.push(
			viewZoneChangeAccessor.addZone({
				afterLineNumber: this.afterLineNumber,
				heightInLines: this.heightInLines,
				domNode: $('div.diagonal-fill'),
			})
		);
	}