diff --git a/Mac/MainWindow/MainWindowController.swift b/Mac/MainWindow/MainWindowController.swift
index 5ed6e1a13..d3e5aab90 100644
--- a/Mac/MainWindow/MainWindowController.swift
+++ b/Mac/MainWindow/MainWindowController.swift
@@ -87,7 +87,9 @@ enum TimelineSourceMode {
 
 		detailSplitViewItem?.minimumThickness = CGFloat(MainWindowController.detailViewMinimumThickness)
 
-		sidebarViewController = splitViewController?.splitViewItems[0].viewController as? SidebarViewController
+		let sidebarSplitViewItem = splitViewController?.splitViewItems[0]
+		sidebarViewController = sidebarSplitViewItem?.viewController as? SidebarViewController
+		sidebarViewController!.splitViewItem = sidebarSplitViewItem
 		sidebarViewController!.delegate = self
 
 		timelineContainerViewController = splitViewController?.splitViewItems[1].viewController as? TimelineContainerViewController
diff --git a/Mac/MainWindow/Sidebar/SidebarViewController.swift b/Mac/MainWindow/Sidebar/SidebarViewController.swift
index 0d571f8ed..a79f899f7 100644
--- a/Mac/MainWindow/Sidebar/SidebarViewController.swift
+++ b/Mac/MainWindow/Sidebar/SidebarViewController.swift
@@ -29,6 +29,8 @@ protocol SidebarDelegate: AnyObject {
 	
 	weak var delegate: SidebarDelegate?
 
+	weak var splitViewItem: NSSplitViewItem?
+
 	private let rebuildTreeAndRestoreSelectionQueue = CoalescingQueue(name: "Rebuild Tree Queue", interval: 1.0)
 	let treeControllerDelegate = WebFeedTreeControllerDelegate()
 	lazy var treeController: TreeController = {
@@ -323,6 +325,7 @@ protocol SidebarDelegate: AnyObject {
 	}
 
 	func focus() {
+		if splitViewItem?.isCollapsed == true { return }
 		outlineView.window?.makeFirstResponderUnlessDescendantIsFirstResponder(outlineView)
 	}