Index: /gtk-qt/trunk/gtk-qt-engine/ChangeLog
===================================================================
--- /gtk-qt/trunk/gtk-qt-engine/ChangeLog (revision 136)
+++ /gtk-qt/trunk/gtk-qt-engine/ChangeLog (revision 140)
@@ -11,4 +11,5 @@
  * Fix a divide by 0 exception in styles where there are no scrollbar buttons
  (cloudcity)
+ * Fix a crash in Firefox's open file dialog
 
 i18n:
Index: /gtk-qt/trunk/gtk-qt-engine/src/engine.cpp
===================================================================
--- /gtk-qt/trunk/gtk-qt-engine/src/engine.cpp (revision 136)
+++ /gtk-qt/trunk/gtk-qt-engine/src/engine.cpp (revision 140)
@@ -642,4 +642,6 @@
 	// Figure out where the slider is.  Hope this rect is the same size as oldSize
 	QRect sliderRect = m_qtStyle->subControlRect(QStyle::CC_ScrollBar, &option, QStyle::SC_ScrollBarSlider, m_dummyScrollBar);
+	if (sliderRect.width() < 0 || sliderRect.height() < 0) // Firefox again :(
+		return;
 	
 	// Get rid of the buttons so we're left with just the scrollbar slider of the size we were asked to draw
Index: /gtk-qt/trunk/gtk-qt-engine/src/rcproperties.cpp
===================================================================
--- /gtk-qt/trunk/gtk-qt-engine/src/rcproperties.cpp (revision 139)
+++ /gtk-qt/trunk/gtk-qt-engine/src/rcproperties.cpp (revision 140)
@@ -175,5 +175,5 @@
 	int availableSize = 200 - qtStyle->subControlRect(QStyle::CC_ScrollBar, &option, QStyle::SC_ScrollBarGroove, scrollBar).width();
 	s_scrollBarButtonCount = s_scrollBarHasForward1 + s_scrollBarHasBack1 + s_scrollBarHasForward2 + s_scrollBarHasBack2; // Evil
-	if (s_scrollBarButtonSize != 0)
+	if (s_scrollBarButtonCount != 0)
 		s_scrollBarButtonSize = availableSize / s_scrollBarButtonCount;
 }