diff --git a/layout/generic/nsBlockFrame.cpp b/layout/generic/nsBlockFrame.cpp
index 0e1aabbff07d..f9c2f4da2318 100644
--- a/layout/generic/nsBlockFrame.cpp
+++ b/layout/generic/nsBlockFrame.cpp
@@ -4118,7 +4118,17 @@ nsBlockFrame::PostPlaceLine(nsBlockReflowState& aState,
   }
 
   // Update xmost
-  nscoord xmost = aLine->mBounds.XMost();
+  nscoord xmost;
+  if(aLine->IsBlock() && aState.GetFlag(BRS_NOWRAP)) {
+    // since the nowrap blocks tend to be as wide as their widest element or
+    // sequel of elements that can't be wrapped anymore (see patch for bug 80817)
+    // let them set xmost to be the width of the widest element of the reflowed line
+    // (patches bug 93363 and other NOWRAP dups)
+    xmost = aMaxElementSize.width;
+  } else {
+    xmost = aLine->mBounds.XMost();
+  }
+
 #ifdef DEBUG
   if (CRAZY_WIDTH(xmost)) {
     ListTag(stdout);
diff --git a/layout/html/base/src/nsBlockFrame.cpp b/layout/html/base/src/nsBlockFrame.cpp
index 0e1aabbff07d..f9c2f4da2318 100644
--- a/layout/html/base/src/nsBlockFrame.cpp
+++ b/layout/html/base/src/nsBlockFrame.cpp
@@ -4118,7 +4118,17 @@ nsBlockFrame::PostPlaceLine(nsBlockReflowState& aState,
   }
 
   // Update xmost
-  nscoord xmost = aLine->mBounds.XMost();
+  nscoord xmost;
+  if(aLine->IsBlock() && aState.GetFlag(BRS_NOWRAP)) {
+    // since the nowrap blocks tend to be as wide as their widest element or
+    // sequel of elements that can't be wrapped anymore (see patch for bug 80817)
+    // let them set xmost to be the width of the widest element of the reflowed line
+    // (patches bug 93363 and other NOWRAP dups)
+    xmost = aMaxElementSize.width;
+  } else {
+    xmost = aLine->mBounds.XMost();
+  }
+
 #ifdef DEBUG
   if (CRAZY_WIDTH(xmost)) {
     ListTag(stdout);