diff --git a/mozilla/layout/mathml/content/src/nsMathMLAtomList.h b/mozilla/layout/mathml/content/src/nsMathMLAtomList.h
index 8641ce2607b..3bd74a56598 100644
--- a/mozilla/layout/mathml/content/src/nsMathMLAtomList.h
+++ b/mozilla/layout/mathml/content/src/nsMathMLAtomList.h
@@ -40,6 +40,7 @@
 
 MATHML_ATOM(abs_, "abs")
 MATHML_ATOM(accent_, "accent")
+MATHML_ATOM(accentunder_, "accentunder")
 MATHML_ATOM(and_, "and")
 MATHML_ATOM(annotation_, "annotation")
 MATHML_ATOM(apply_, "apply")
@@ -71,6 +72,7 @@ MATHML_ATOM(exp_, "exp")
 MATHML_ATOM(factorial_, "factorial")
 MATHML_ATOM(fence_, "fence")
 MATHML_ATOM(fn_, "fn")
+MATHML_ATOM(fontstyle_, "fontstyle")
 MATHML_ATOM(forall_, "forall")
 MATHML_ATOM(form_, "form")
 MATHML_ATOM(geq_, "geq")