After further thought. It sounds like this is maybe just some naming confusion with the names of these functions. I’ll use the dynamicUpdate property of the navigator as suggested.

You may wish to consider clarifying their names to better reflect their actual difference in usage? Maybe something like rangeChangingAutomatic and rangeChangingManual or similar. And also perhaps fix/update/eliminate the event.type parameter since it doesn’t sound like it provides much value or was a remnant of an old implementation.