diff --git a/lib/editor-client.js b/lib/editor-client.js
index a25373ee2..5c68ae9c9 100644
--- a/lib/editor-client.js
+++ b/lib/editor-client.js
@@ -138,7 +138,11 @@ firepad.EditorClient = (function () {
     var compose = this.undoManager.undoStack.length > 0 &&
       inverse.shouldBeComposedWithInverted(last(this.undoManager.undoStack).wrapped);
     var inverseMeta = new SelfMeta(this.cursor, cursorBefore);
-    this.undoManager.add(new WrappedOperation(inverse, inverseMeta), compose);
+    
+    if (this.editorAdapter.ready) {
+      this.undoManager.add(new WrappedOperation(inverse, inverseMeta), compose);
+    }
+    
     this.applyClient(textOperation);
   };
 
diff --git a/lib/firepad.js b/lib/firepad.js
index f8fe6993e..68997a952 100644
--- a/lib/firepad.js
+++ b/lib/firepad.js
@@ -132,6 +132,8 @@ firepad.Firepad = (function(global) {
       if (defaultText && self.isHistoryEmpty()) {
         self.setText(defaultText);
       }
+      
+      self.editorAdapter_.ready = true;
 
       self.trigger('ready');
     });
diff --git a/lib/text-operation.js b/lib/text-operation.js
index 4e1d26f02..3e9b98af9 100644
--- a/lib/text-operation.js
+++ b/lib/text-operation.js
@@ -452,6 +452,11 @@ firepad.TextOperation = (function () {
       // delete key.
       return (startB + simpleB.chars === startA) || startA === startB;
     }
+    
+    // undo text replace in one go
+    if (simpleA.isDelete() && simpleB.isInsert()) {
+      return startA === startB;
+    }
 
     return false;
   };
diff --git a/lib/undo-manager.js b/lib/undo-manager.js
index c73ef1308..aaf94e42b 100644
--- a/lib/undo-manager.js
+++ b/lib/undo-manager.js
@@ -9,7 +9,7 @@ firepad.UndoManager = (function () {
 
   // Create a new UndoManager with an optional maximum history size.
   function UndoManager (maxItems) {
-    this.maxItems  = maxItems || 50;
+    this.maxItems  = maxItems || 500;
     this.state = NORMAL_STATE;
     this.dontCompose = false;
     this.undoStack = [];