--- a/layout/xul/nsSliderFrame.cpp
+++ b/layout/xul/nsSliderFrame.cpp
@@ -88,17 +88,16 @@ nsSliderFrame::nsSliderFrame(nsStyleCont
   mScrollingWithAPZ(false),
   mSuppressionActive(false)
 {
 }
 
 // stop timer
 nsSliderFrame::~nsSliderFrame()
 {
-  MOZ_ASSERT(!mSuppressionActive, "Should have un-suppress via StopDrag() first.");
   if (mSuppressionActive) {
     APZCCallbackHelper::SuppressDisplayport(false, PresContext() ?
                                                    PresContext()->PresShell() :
                                                    nullptr);
   }
 }
 
 void