Omitting acces to invalid index
// do not create a BraceInset if they were written by LyX
// this helps to keep the annoyance of "a choose b" to a minimum
// But create a BraceInset if a script follows (#9348)
- InsetMathBrace const * mb = ar[0]->asBraceInset();
+ InsetMathBrace const * mb;
+ if (ar.size() > 0)
+ mb = ar[0]->asBraceInset();
if (ar.size() == 1 && (ar[0]->extraBraces()
|| (mb && mb->cell(0).size()
&& !mb->cell(0)[0].nucleus()->asScriptInset())))