diff --git a/image/DecoderFactory.cpp b/image/DecoderFactory.cpp
index f36f03c7f2..d2cdd79f70 100644
--- a/image/DecoderFactory.cpp
+++ b/image/DecoderFactory.cpp
@@ -244,7 +244,12 @@ nsresult DecoderFactory::CreateAnimationDecoder(
   }
 
   MOZ_ASSERT(aType == DecoderType::GIF || aType == DecoderType::PNG ||
-                 aType == DecoderType::WEBP || aType == DecoderType::AVIF,
+                 aType == DecoderType::WEBP || aType == DecoderType::AVIF
+#ifdef MOZ_JXL
+                 || aType == DecoderType::JXL,
+#else
+             ,
+#endif
              "Calling CreateAnimationDecoder for non-animating DecoderType");
 
   // Create an anonymous decoder. Interaction with the SurfaceCache and the
@@ -299,7 +304,12 @@ already_AddRefed<Decoder> DecoderFactory::CloneAnimationDecoder(
   // rediscover it is animated).
   DecoderType type = aDecoder->GetType();
   MOZ_ASSERT(type == DecoderType::GIF || type == DecoderType::PNG ||
-                 type == DecoderType::WEBP || type == DecoderType::AVIF,
+                 type == DecoderType::WEBP || type == DecoderType::AVIF
+#ifdef MOZ_JXL
+                 || aType == DecoderType::JXL,
+#else
+             ,
+#endif
              "Calling CloneAnimationDecoder for non-animating DecoderType");
 
   RefPtr<Decoder> decoder = GetDecoder(type, nullptr, /* aIsRedecode = */ true);