diff --git a/layout/generic/nsHTMLReflowState.h b/layout/generic/nsHTMLReflowState.h
index 7a84d8612b4f..e885eeae73c9 100644
--- a/layout/generic/nsHTMLReflowState.h
+++ b/layout/generic/nsHTMLReflowState.h
@@ -247,10 +247,9 @@ struct nsHTMLReflowState : public nsCSSOffsetState {
const nsHTMLReflowState *mCBReflowState;
// the available width in which to reflow the frame. The space
- // represents the amount of room for the frame's border, padding,
- // and content area (not the margin area. The parent frame deals
- // with the child frame's margins). The frame size you choose should
- // fit within the available width.
+ // represents the amount of room for the frame's margin, border,
+ // padding, and content area. The frame size you choose should fit
+ // within the available width.
nscoord availableWidth;
// A value of NS_UNCONSTRAINEDSIZE for the available height means