diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 59df88339d4..5efdf40b60a 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -1266,7 +1266,7 @@ def typeNeedsCx(type, retVal=False):
 # Returns a conversion behavior suitable for a type
 def getConversionConfigForType(type, isEnforceRange, isClamp, treatNullAs):
     if type.isSequence():
-        return getConversionConfigForType(type.unroll(), isEnforceRange, isClamp, treatNullAs)
+        return getConversionConfigForType(innerContainerType(type), isEnforceRange, isClamp, treatNullAs)
     if type.isDOMString():
         assert not isEnforceRange and not isClamp