So in NSCollectionView I left click the background and start dragging to make the 'selection box' (is that what we call it?) I have a mouse with separate left and right click buttons (i.e., not an Apple Magic Mouse). Now if I accidentally hit the right click while I'm still dragging the selection box..... the right click context menu shows up in the middle of mouse dragging and the selection box freezes on screen. Besides the visual disruption this sometimes results in weird behavior. Sometimes mouse clicks stop responding for awhile in the window and I gotta click around a bunch of times until I guess the run loop "unclogs." I'm able to reproduce in Finder Icon view so it isn't just me. Steps to Reproduce: A mouse with separate buttons for left and right click. Open Finder window in icon view. Left click the background and start dragging to make the gray selection box. While dragging the mouse as you are selecting click right-click in the middle of the drag. The selection box freezes on screen. Expected Behavior: -Right click event and left mouse drag event normally shouldn't overlap. If left mouse is being dragged the right click event should be blocked. Let me know if this is Feedback worthy.