diff --git a/gfx/2d/Path.cpp b/gfx/2d/Path.cpp
index a276609bef15..35c0232b1af2 100644
--- a/gfx/2d/Path.cpp
+++ b/gfx/2d/Path.cpp
@@ -250,12 +250,19 @@ FlattenBezierCurveSegment(const BezierControlPoints &aControlPoints,
     Point cp21 = currentCP.mCP2 - currentCP.mCP3;
     Point cp31 = currentCP.mCP3 - currentCP.mCP1;
 
-    Float s3 = (cp31.x * cp21.y - cp31.y * cp21.x) / hypotf(cp21.x, cp21.y);
-
-    t = 2 * Float(sqrt(aTolerance / (3. * std::abs(s3))));
+    /* To remove divisions and check for divide-by-zero, this is optimized from:
+     * Float s3 = (cp31.x * cp21.y - cp31.y * cp21.x) / hypotf(cp21.x, cp21.y);
+     * t = 2 * Float(sqrt(aTolerance / (3. * std::abs(s3))));
+     */
+    Float cp21x31 = cp31.x * cp21.y - cp31.y * cp21.x;
+    Float h = hypotf(cp21.x, cp21.y);
+    if (cp21x31 * h == 0) {
+      break;
+    }
 
+    Float s3inv = h / cp21x31;
+    t = 2 * Float(sqrt(aTolerance * std::abs(s3inv) / 3.));
     if (t >= 1.0f) {
-      aSink->LineTo(aControlPoints.mCP4);
       break;
     }
 
@@ -264,6 +271,8 @@ FlattenBezierCurveSegment(const BezierControlPoints &aControlPoints,
 
     aSink->LineTo(currentCP.mCP1);
   }
+
+  aSink->LineTo(currentCP.mCP4);
 }
 
 static inline void