diff --git a/lib/ace/virtual_renderer.js b/lib/ace/virtual_renderer.js
index b2d64a5c..f08e24cb 100644
--- a/lib/ace/virtual_renderer.js
+++ b/lib/ace/virtual_renderer.js
@@ -134,7 +134,8 @@ var VirtualRenderer = function(container, theme) {
         width: 0,
         height: 0,
         scrollerHeight: 0,
-        scrollerWidth: 0
+        scrollerWidth: 0,
+        $dirty: true
     };
 
     this.layerConfig = {
@@ -223,6 +224,9 @@ var VirtualRenderer = function(container, theme) {
     **/
     this.setSession = function(session) {
         this.session = session;
+        
+        if (this.scrollMargin.top && session.getScrollTop() <= 0)
+            session.setScrollTop(-this.scrollMargin.top);
 
         this.scroller.className = "ace_scroller";
 
@@ -232,7 +236,6 @@ var VirtualRenderer = function(container, theme) {
         this.$gutterLayer.setSession(session);
         this.$textLayer.setSession(session);
         this.$loop.schedule(this.CHANGE_FULL);
-
     };
 
     /**
@@ -300,6 +303,12 @@ var VirtualRenderer = function(container, theme) {
     };
 
     this.$changes = 0;
+    this.$updateSizeAsync = function() {
+        if (this.$loop.pending)
+            this.$size.$dirty = true;
+        else
+            this.onResize();
+    };
     /**
     * [Triggers a resize of the editor.]{: #VirtualRenderer.onResize}
     * @param {Boolean} force If `true`, recomputes the size, even if the height and width haven't changed
@@ -325,7 +334,6 @@ var VirtualRenderer = function(container, theme) {
             height = el.clientHeight || el.scrollHeight;
         if (!width)
             width = el.clientWidth || el.scrollWidth;
-
         var changes = this.$updateCachedSize(force, gutterWidth, width, height);
         
         // console.log("resizing to", width, height, JSON.stringify(this.$size))
@@ -342,7 +350,7 @@ var VirtualRenderer = function(container, theme) {
             this.$gutterLayer.$padding = null;
 
         if (force)
-            this.$renderChanges(changes, true);
+            this.$renderChanges(changes | this.$changes, true);
         else
             this.$loop.schedule(changes | this.$changes);
 
@@ -371,7 +379,7 @@ var VirtualRenderer = function(container, theme) {
             this.scrollBarV.element.style.bottom = this.scrollBarH.getHeight() + "px";
 
             if (this.session) {
-                this.session.setScrollTop(this.getScrollTop());
+                //this.session.setScrollTop(this.getScrollTop());
                 changes = changes | this.CHANGE_SCROLL;
             }
         }
@@ -399,6 +407,9 @@ var VirtualRenderer = function(container, theme) {
                 changes = changes | this.CHANGE_FULL;
         }
         
+        if (size.$dirty)
+            size.$dirty = !width && !height;
+
         if (changes)
             this._signal("resize", oldSize);
 
@@ -410,9 +421,11 @@ var VirtualRenderer = function(container, theme) {
         if (gutterWidth != this.gutterWidth)
             this.$changes |= this.$updateCachedSize(true, gutterWidth, this.$size.width, this.$size.height);
 
-        if (this.session.getUseWrapMode() && this.adjustWrapLimit())
+        if (this.session.getUseWrapMode() && this.adjustWrapLimit()) {
             this.$loop.schedule(this.CHANGE_FULL);
-        else {
+        } else if (this.$size.$dirty) {
+            this.$loop.schedule(this.CHANGE_FULL);
+        } else {
             this.$computeLayerConfig();
             this.$loop.schedule(this.CHANGE_MARKER);
         }
@@ -692,6 +705,8 @@ var VirtualRenderer = function(container, theme) {
         sm.left = left|0;
         sm.v = sm.top + sm.bottom;
         sm.h = sm.left + sm.right;
+        if (sm.top && this.scrollTop <= 0 && this.session)
+            this.session.setScrollTop(sm.top);
         this.updateFull();
     };
 
@@ -744,7 +759,7 @@ var VirtualRenderer = function(container, theme) {
             this.$changes |= changes;
             return; 
         } 
-        if (!this.$size.width) {
+        if (this.$size.$dirty) {
             this.$changes |= changes;
             return this.onResize(true);
         }
@@ -972,6 +987,7 @@ var VirtualRenderer = function(container, theme) {
         this.content.style.height = minHeight + "px";
 
         return changes;
+        return changes;
     };
 
     this.$updateLines = function() {