diff --git a/mozilla/layout/forms/nsTextControlFrame.cpp b/mozilla/layout/forms/nsTextControlFrame.cpp
index fc2420cfd0d..be6fc196642 100644
--- a/mozilla/layout/forms/nsTextControlFrame.cpp
+++ b/mozilla/layout/forms/nsTextControlFrame.cpp
@@ -1490,6 +1490,14 @@ nsTextControlFrame::CalculateSizeStandard(nsIPresContext*       aPresContext,
     }
     // Now add the extra padding on (so that small input sizes work well)
     aDesiredSize.width += internalPadding;
+  } else {
+    // This is to account for the anonymous <br> having a 1 twip width
+    // in Full Standards mode, see BRFrame::Reflow and bug 228752.
+    nsCompatibility mode;
+    aPresContext->GetCompatibilityMode(&mode);
+    if (mode == eCompatibility_FullStandards) {
+      aDesiredSize.width += 1;
+    }
   }
 
   // Set the height equal to total number of rows (times the height of each
diff --git a/mozilla/layout/generic/nsBRFrame.cpp b/mozilla/layout/generic/nsBRFrame.cpp
index 5504769315a..4be7091b312 100644
--- a/mozilla/layout/generic/nsBRFrame.cpp
+++ b/mozilla/layout/generic/nsBRFrame.cpp
@@ -184,6 +184,8 @@ BRFrame::Reflow(nsIPresContext* aPresContext,
       // code in nsLineLayout::VerticalAlignFrames that zaps minY/maxY
       // if the width is zero.
       // XXX This also fixes bug 10036!
+      // Warning: nsTextControlFrame::CalculateSizeStandard depends on
+      // the following line, see bug 228752.
       aMetrics.width = 1;
 
       // Update max-element-width to keep us honest
diff --git a/mozilla/layout/html/base/src/nsBRFrame.cpp b/mozilla/layout/html/base/src/nsBRFrame.cpp
index 5504769315a..4be7091b312 100644
--- a/mozilla/layout/html/base/src/nsBRFrame.cpp
+++ b/mozilla/layout/html/base/src/nsBRFrame.cpp
@@ -184,6 +184,8 @@ BRFrame::Reflow(nsIPresContext* aPresContext,
       // code in nsLineLayout::VerticalAlignFrames that zaps minY/maxY
       // if the width is zero.
       // XXX This also fixes bug 10036!
+      // Warning: nsTextControlFrame::CalculateSizeStandard depends on
+      // the following line, see bug 228752.
       aMetrics.width = 1;
 
       // Update max-element-width to keep us honest
diff --git a/mozilla/layout/html/forms/src/nsTextControlFrame.cpp b/mozilla/layout/html/forms/src/nsTextControlFrame.cpp
index fc2420cfd0d..be6fc196642 100644
--- a/mozilla/layout/html/forms/src/nsTextControlFrame.cpp
+++ b/mozilla/layout/html/forms/src/nsTextControlFrame.cpp
@@ -1490,6 +1490,14 @@ nsTextControlFrame::CalculateSizeStandard(nsIPresContext*       aPresContext,
     }
     // Now add the extra padding on (so that small input sizes work well)
     aDesiredSize.width += internalPadding;
+  } else {
+    // This is to account for the anonymous <br> having a 1 twip width
+    // in Full Standards mode, see BRFrame::Reflow and bug 228752.
+    nsCompatibility mode;
+    aPresContext->GetCompatibilityMode(&mode);
+    if (mode == eCompatibility_FullStandards) {
+      aDesiredSize.width += 1;
+    }
   }
 
   // Set the height equal to total number of rows (times the height of each