--- a/dom/animation/KeyframeEffectReadOnly.cpp
+++ b/dom/animation/KeyframeEffectReadOnly.cpp
@@ -301,19 +301,20 @@ KeyframeEffectReadOnly::UpdateProperties
 
   if (!mDocument->IsStyledByServo()) {
     DoUpdateProperties(Move(aStyleContext));
     return;
   }
 
   const ServoComputedValues* currentStyle =
     aStyleContext->StyleSource().AsServoComputedValues();
+  // FIXME: Remove GetParentAllowServo() in Bug 1349004.
   const ServoComputedValues* parentStyle =
-    aStyleContext->GetParent()
-      ? aStyleContext->GetParent()->StyleSource().AsServoComputedValues()
+    aStyleContext->GetParentAllowServo()
+      ? aStyleContext->GetParentAllowServo()->StyleSource().AsServoComputedValues()
       : nullptr;
 
   const ServoComputedValuesWithParent servoValues = { currentStyle, parentStyle };
   DoUpdateProperties(servoValues);
 }
 
 void
 KeyframeEffectReadOnly::UpdateProperties(