 
 	private var articles = [Article]() {
 		didSet {
-			tableView.reloadData()
+			if articles != oldValue {
+				clearUndoableCommands()
+				tableView.reloadData()
+			}
 		}
 	}
 

		guard let undoManager = undoManager, let markAllReadCommand = MarkAllReadCommand(initialArticles: articles, undoManager: undoManager) else {
			return
		}
		markAllReadCommand.perform()
	}
	
	// MARK: - Actions

	private func pushUndoableCommand(_ undoableCommand: UndoableCommand) {


		undoableCommands.forEach { undoManager.removeAllActions(withTarget: $0) }
		undoableCommands = [UndoableCommand]()
	}

	// MARK: - Actions

	@objc func openArticleInBrowser(_ sender: AnyObject) {
		
