Fixed bug causing regions to close suddenly.

src/AddIns/DisplayBindings/AvalonEdit.AddIn/Src/ParserFoldingStrategy.cs

@@ -23,7 +23,6 @@ namespace ICSharpCode.AvalonEdit.AddIn
 		readonly FoldingManager foldingManager;
 		
 		TextArea textArea;
-		bool isFirstUpdate = true;
 		
 		public FoldingManager FoldingManager {
 			get { return foldingManager; }
@@ -54,8 +53,6 @@ namespace ICSharpCode.AvalonEdit.AddIn
 			IEnumerable<NewFolding> newFoldings = parseInfo.GetFoldings(textArea.Document, out firstErrorOffset);
 			newFoldings = newFoldings.OrderBy(f => f.StartOffset);
 			foldingManager.UpdateFoldings(newFoldings, firstErrorOffset);
-			
-			isFirstUpdate = false;
 		}
 	}
 }

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Folding/FoldingManager.cs

@@ -23,6 +23,7 @@ namespace ICSharpCode.AvalonEdit.Folding
 		
 		internal readonly List<TextView> textViews = new List<TextView>();
 		readonly TextSegmentCollection<FoldingSection> foldings;
+		bool isFirstUpdate = true;
 		
 		#region Constructor
 		/// <summary>
@@ -261,7 +262,10 @@ namespace ICSharpCode.AvalonEdit.Folding
 					// no matching current folding; create a new one:
 					section = this.CreateFolding(newFolding.StartOffset, newFolding.EndOffset);
 					// auto-close #regions only when opening the document
-					section.IsFolded = newFolding.DefaultClosed;
+					if (isFirstUpdate) {
+						section.IsFolded = newFolding.DefaultClosed;
+						isFirstUpdate = false;
+					}
 					section.Tag = newFolding;
 				}
 				section.Title = newFolding.Name;