diff --git a/layout/generic/nsRubyBaseContainerFrame.cpp b/layout/generic/nsRubyBaseContainerFrame.cpp
index 765330553698..779e9187246d 100644
--- a/layout/generic/nsRubyBaseContainerFrame.cpp
+++ b/layout/generic/nsRubyBaseContainerFrame.cpp
@@ -273,14 +273,6 @@ nsRubyBaseContainerFrame::Reflow(nsPresContext* aPresContext,
 
   aStatus = NS_FRAME_COMPLETE;
   WritingMode lineWM = aReflowState.mLineLayout->GetWritingMode();
-  WritingMode frameWM = aReflowState.GetWritingMode();
-  LogicalMargin borderPadding = aReflowState.ComputedLogicalBorderPadding();
-  nscoord startEdge = borderPadding.IStart(frameWM);
-  nscoord endEdge = aReflowState.AvailableISize() - borderPadding.IEnd(frameWM);
-
-  aReflowState.mLineLayout->BeginSpan(this, &aReflowState,
-                                      startEdge, endEdge, &mBaseline);
-
   LogicalSize availSize(lineWM, aReflowState.AvailableWidth(),
                         aReflowState.AvailableHeight());
 
@@ -339,6 +331,13 @@ nsRubyBaseContainerFrame::Reflow(nsPresContext* aPresContext,
                                 false, false, lineWM, containerWidth);
   }
 
+  WritingMode frameWM = aReflowState.GetWritingMode();
+  LogicalMargin borderPadding = aReflowState.ComputedLogicalBorderPadding();
+  nscoord startEdge = borderPadding.IStart(frameWM);
+  nscoord endEdge = aReflowState.AvailableISize() - borderPadding.IEnd(frameWM);
+  aReflowState.mLineLayout->BeginSpan(this, &aReflowState,
+                                      startEdge, endEdge, &mBaseline);
+
   // Reflow pairs excluding any span
   nscoord pairsISize = ReflowPairs(aPresContext, aReflowState,
                                    rtcReflowStates, aStatus);