Some built in AppKit components temporarily "pause" NSTrackingArea updates while their content is being scrolled or resized. For example, if you inspect tracking areas using the Quartz Debug tool, you can see that tracking areas embedded in an NSScrollView don't move onscreen as the content is being scrolled, and only update when scrolling ends. Tracking areas within NSSplitView panes similarly don't update while the panes are being resized. How do these components achieve this behavior?

I'm working on a custom scrolling component that handles scrollWheel events and enters a mouse tracking loop as described here and I'd like to replicate this behavior as a performance improvement.