* SUMMARY From Bug 138387 it seems the TimelineViews are updating even though they are not visible. This seems like a lot of unnecessary work and can slow down interacting with the other views in the inspector, especially on page loads.
Maybe not all TimelineViews, perhaps just the OverviewTimelineView.
<rdar://problem/18876212>
*** This bug has been marked as a duplicate of bug 141293 ***