RV event for sources visible changed

Just throwing this out there; because RV lacks an event sent when the visible sources change, does anyone have a cool workaround they use?

My most efficient method has been to create an in-memory cache using sequenceBoundaries and bisect the list to find the current source. Does anyone have something better?

To SG/RV; a native event for this would be awesome.

Cheers,
-Kessler