Alter Navigation to take the time since the last navigation into account. If less than 0.5 seconds, do a replacement automatically.

ILSpy/MainWindow.xaml.cs

@@ -587,7 +587,7 @@ namespace ICSharpCode.ILSpy
 			var currentSelection = treeView.SelectedItems.OfType<SharpTreeNode>().ToList();
 			var state = decompilerTextView.GetState();
 			var combinedState = Tuple.Create(currentSelection, state);
-			history.Replace(combinedState);
+			history.Record(combinedState, replace: true, clearForward: false);
 			var newState = forward ? history.GoForward() : history.GoBack();
 
 			ignoreDecompilationRequests = true;

ILSpy/NavigationHistory.cs

@@ -14,6 +14,9 @@ namespace ICSharpCode.ILSpy
 	internal sealed class NavigationHistory<T>
 		where T : class
 	{
+		private const double NavigationSecondsBeforeNewEntry = 0.5;
+
+		private DateTime lastNavigationTime = DateTime.MinValue;
 		T current;
 		List<T> back = new List<T>();
 		List<T> forward = new List<T>();
@@ -54,18 +57,24 @@ namespace ICSharpCode.ILSpy
 			forward.Clear();
 		}
 		
-		public void Replace(T node)
+		public void Record(T node, bool replace = false, bool clearForward = true)
 		{
-			current = node;
+			var navigationTime = DateTime.Now;
-		}
+			var period = navigationTime - lastNavigationTime;
 
-		public void Record(T node)
+			if (period.TotalSeconds < NavigationSecondsBeforeNewEntry || replace) {
-		{
+				current = node;
-			if (current != null)
+			} else {
-				back.Add(current);
+				if (current != null)
+					back.Add(current);
 
-			forward.Clear();
+				current = node;
-			current = node;
+			}
+
+			if (clearForward)
+				forward.Clear();
+
+			lastNavigationTime = navigationTime;
 		}
 	}
 }