diff --git a/src/Avalonia.Controls/Presenters/TextPresenter.cs b/src/Avalonia.Controls/Presenters/TextPresenter.cs
index c241466aea..bda660be51 100644
--- a/src/Avalonia.Controls/Presenters/TextPresenter.cs
+++ b/src/Avalonia.Controls/Presenters/TextPresenter.cs
@@ -223,11 +223,11 @@ namespace Avalonia.Controls.Presenters
 
             if (PasswordChar != default(char))
             {
-                result = base.CreateFormattedText(constraint, new string(PasswordChar, Text.Length));
+                result = base.CreateFormattedText(constraint, new string(PasswordChar, text?.Length ?? 0));
             }
             else
             {
-                result = base.CreateFormattedText(constraint, Text);
+                result = base.CreateFormattedText(constraint, text);
             }
 
             var selectionStart = SelectionStart;
diff --git a/src/Avalonia.Controls/TextBlock.cs b/src/Avalonia.Controls/TextBlock.cs
index 1fee309360..e7cf666589 100644
--- a/src/Avalonia.Controls/TextBlock.cs
+++ b/src/Avalonia.Controls/TextBlock.cs
@@ -111,6 +111,8 @@ namespace Avalonia.Controls
         /// </summary>
         public TextBlock()
         {
+            _text = string.Empty;
+
             Observable.Merge(
                 this.GetObservable(TextProperty).Select(_ => Unit.Default),
                 this.GetObservable(TextAlignmentProperty).Select(_ => Unit.Default),
diff --git a/src/Avalonia.Controls/ToolTip.cs b/src/Avalonia.Controls/ToolTip.cs
index e45f30f818..464e4188d2 100644
--- a/src/Avalonia.Controls/ToolTip.cs
+++ b/src/Avalonia.Controls/ToolTip.cs
@@ -34,25 +34,25 @@ namespace Avalonia.Controls
         /// Defines the ToolTip.Placement property.
         /// </summary>
         public static readonly AttachedProperty<PlacementMode> PlacementProperty =
-            AvaloniaProperty.RegisterAttached<Popup, Control, PlacementMode>("Placement", defaultValue: PlacementMode.Pointer);
+            AvaloniaProperty.RegisterAttached<ToolTip, Control, PlacementMode>("Placement", defaultValue: PlacementMode.Pointer);
 
         /// <summary>
         /// Defines the ToolTip.HorizontalOffset property.
         /// </summary>
         public static readonly AttachedProperty<double> HorizontalOffsetProperty =
-            AvaloniaProperty.RegisterAttached<Popup, Control, double>("HorizontalOffset");
+            AvaloniaProperty.RegisterAttached<ToolTip, Control, double>("HorizontalOffset");
 
         /// <summary>
         /// Defines the ToolTip.VerticalOffset property.
         /// </summary>
         public static readonly AttachedProperty<double> VerticalOffsetProperty =
-            AvaloniaProperty.RegisterAttached<Popup, Control, double>("VerticalOffset", 20);
+            AvaloniaProperty.RegisterAttached<ToolTip, Control, double>("VerticalOffset", 20);
 
         /// <summary>
         /// Defines the ToolTip.ShowDelay property.
         /// </summary>
         public static readonly AttachedProperty<int> ShowDelayProperty =
-            AvaloniaProperty.RegisterAttached<Popup, Control, int>("ShowDelay", 400);
+            AvaloniaProperty.RegisterAttached<ToolTip, Control, int>("ShowDelay", 400);
 
         /// <summary>
         /// Stores the curernt <see cref="ToolTip"/> instance in the control.
diff --git a/src/Markup/Avalonia.Markup/Data/Parsers/ArgumentListParser.cs b/src/Markup/Avalonia.Markup/Data/Parsers/ArgumentListParser.cs
index 563b372c78..05b3b29be0 100644
--- a/src/Markup/Avalonia.Markup/Data/Parsers/ArgumentListParser.cs
+++ b/src/Markup/Avalonia.Markup/Data/Parsers/ArgumentListParser.cs
@@ -51,10 +51,10 @@ namespace Avalonia.Markup.Data.Parsers
                     }
                 }
 
-                throw new ExpressionParseException(r.Position, "Expected ']'.");
+                throw new ExpressionParseException(r.Position, $"Expected '{close}'.");
             }
 
-            return null;
+            throw new ExpressionParseException(r.Position, $"Expected '{open}'.");
         }
     }
 }
diff --git a/src/Markup/Avalonia.Markup/Data/Parsers/ExpressionParser.cs b/src/Markup/Avalonia.Markup/Data/Parsers/ExpressionParser.cs
index 93ddf77376..f31f6eccb7 100644
--- a/src/Markup/Avalonia.Markup/Data/Parsers/ExpressionParser.cs
+++ b/src/Markup/Avalonia.Markup/Data/Parsers/ExpressionParser.cs
@@ -40,6 +40,10 @@ namespace Avalonia.Markup.Data.Parsers
                     case State.AttachedProperty:
                         state = ParseAttachedProperty(r, nodes);
                         break;
+
+                    case State.Indexer:
+                        state = ParseIndexer(r, nodes);
+                        break;
                 }
             }
 
@@ -67,6 +71,10 @@ namespace Avalonia.Markup.Data.Parsers
             {
                 return State.AttachedProperty;
             }
+            else if (PeekOpenBracket(r))
+            {
+                return State.Indexer;
+            }
             else
             {
                 var identifier = IdentifierParser.Parse(r);
@@ -92,20 +100,9 @@ namespace Avalonia.Markup.Data.Parsers
                 nodes.Add(new StreamNode());
                 return State.AfterMember;
             }
-            else
+            else if (PeekOpenBracket(r))
             {
-                var args = ArgumentListParser.Parse(r, '[', ']');
-
-                if (args != null)
-                {
-                    if (args.Count == 0)
-                    {
-                        throw new ExpressionParseException(r.Position, "Indexer may not be empty.");
-                    }
-
-                    nodes.Add(new IndexerNode(args));
-                    return State.AfterMember;
-                }
+                return State.Indexer;
             }
 
             return State.End;
@@ -151,6 +148,19 @@ namespace Avalonia.Markup.Data.Parsers
             return State.AfterMember;
         }
 
+        private State ParseIndexer(Reader r, List<ExpressionNode> nodes)
+        {
+            var args = ArgumentListParser.Parse(r, '[', ']');
+
+            if (args.Count == 0)
+            {
+                throw new ExpressionParseException(r.Position, "Indexer may not be empty.");
+            }
+
+            nodes.Add(new IndexerNode(args));
+            return State.AfterMember;
+        }
+        
         private static bool ParseNot(Reader r)
         {
             return !r.End && r.TakeIf('!');
@@ -166,6 +176,11 @@ namespace Avalonia.Markup.Data.Parsers
             return !r.End && r.TakeIf('(');
         }
 
+        private static bool PeekOpenBracket(Reader r)
+        {
+            return !r.End && r.Peek == '[';
+        }
+
         private static bool ParseStreamOperator(Reader r)
         {
             return !r.End && r.TakeIf('^');
@@ -177,6 +192,7 @@ namespace Avalonia.Markup.Data.Parsers
             AfterMember,
             BeforeMember,
             AttachedProperty,
+            Indexer,
             End,
         }
     }
diff --git a/tests/Avalonia.Controls.UnitTests/Presenters/TextPresenter_Tests.cs b/tests/Avalonia.Controls.UnitTests/Presenters/TextPresenter_Tests.cs
new file mode 100644
index 0000000000..23dae8f341
--- /dev/null
+++ b/tests/Avalonia.Controls.UnitTests/Presenters/TextPresenter_Tests.cs
@@ -0,0 +1,40 @@
+using Avalonia.Controls.Presenters;
+using Xunit;
+
+namespace Avalonia.Controls.UnitTests.Presenters
+{
+    public class TextPresenter_Tests
+    {
+        [Fact]
+        public void TextPresenter_Can_Contain_Null_With_Password_Char_Set()
+        {
+            var target = new TextPresenter
+            {
+                PasswordChar = '*'
+            };
+
+            Assert.NotNull(target.FormattedText);
+        }
+
+        [Fact]
+        public void TextPresenter_Can_Contain_Null_WithOut_Password_Char_Set()
+        {
+            var target = new TextPresenter();
+
+            Assert.NotNull(target.FormattedText);
+        }
+
+        [Fact]
+        public void Text_Presenter_Replaces_Formatted_Text_With_Password_Char()
+        {
+            var target = new TextPresenter
+            {
+                PasswordChar = '*',
+                Text = "Test"
+            };
+
+            Assert.NotNull(target.FormattedText);
+            Assert.Equal("****", target.FormattedText.Text);
+        }
+    }
+}
diff --git a/tests/Avalonia.Controls.UnitTests/TextBlockTests.cs b/tests/Avalonia.Controls.UnitTests/TextBlockTests.cs
index b8886456dd..9a1140fc05 100644
--- a/tests/Avalonia.Controls.UnitTests/TextBlockTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/TextBlockTests.cs
@@ -15,5 +15,15 @@ namespace Avalonia.Controls.UnitTests
                 BindingMode.OneWay,
                 TextBlock.TextProperty.GetMetadata(typeof(TextBlock)).DefaultBindingMode);
         }
+
+        [Fact]
+        public void Default_Text_Value_Should_Be_EmptyString()
+        {
+            var textBlock = new TextBlock();
+
+            Assert.Equal(
+                "",
+                textBlock.Text);
+        }
     }
 }
diff --git a/tests/Avalonia.Markup.UnitTests/Data/ExpressionObserverTests_Indexer.cs b/tests/Avalonia.Markup.UnitTests/Data/ExpressionObserverTests_Indexer.cs
index a68213baee..1bdbf0d895 100644
--- a/tests/Avalonia.Markup.UnitTests/Data/ExpressionObserverTests_Indexer.cs
+++ b/tests/Avalonia.Markup.UnitTests/Data/ExpressionObserverTests_Indexer.cs
@@ -338,6 +338,18 @@ namespace Avalonia.Markup.UnitTests.Data
             GC.KeepAlive(data);
         }
 
+        [Fact]
+        public async Task Indexer_Only_Binding_Works()
+        {
+            var data = new[] { 1, 2, 3 };
+
+            var target = new ExpressionObserver(data, "[1]");
+
+            var value = await target.Take(1);
+
+            Assert.Equal(data[1], value);
+        }
+
         private class NonIntegerIndexer : NotifyingBase
         {
             private readonly Dictionary<string, string> _storage = new Dictionary<string, string>();