The attached patch fixes bug 4424
http://bugzilla.lyx.org/show_bug.cgi?id=4424
André, what was the reason that mbox instead of \textrm was used?
regards Uwe
Index: InsetMathNest.cpp
===================================================================
--- InsetMathNest.cpp (revision 22152)
+++ InsetMathNest.cpp (working copy)
@@ -880,7 +880,7 @@
docstring const save_selection = grabAndEraseSelection(cur);
selClearOrDel(cur);
//cur.plainInsert(MathAtom(new InsetMathMBox(cur.bv())));
- cur.plainInsert(MathAtom(new InsetMathBox(from_ascii("mbox"))));
+ cur.plainInsert(MathAtom(new InsetMathBox(from_ascii("textrm"))));
cur.posBackward();
cur.pushBackward(*cur.nextInset());
cur.niceInsert(save_selection);
