if (!nuc().empty())
ms << nuc();
else
+ // TODO: is this empty <mrow> required?
ms << CTag("mrow");
+ // No need to wrap these in an <mrow>, as it's done by MathExtern.
+ // More details in https://www.lyx.org/trac/ticket/12221#comment:10.
if (d)
- ms << MTag("mrow") << down() << ETag("mrow");
+ ms << down();
if (u)
- ms << MTag("mrow") << up() << ETag("mrow");
+ ms << up();
ms << ETag(tag);
}