[LyX/master] Re-fix #11146 with recent LaTeX

[Richard Kimberly Heck]

On 11/20/19 5:43 AM, Juergen Spitzmueller wrote:
> commit e75fa6f3ac5735dfcd588acb5c187556bface16d
> Author: Juergen Spitzmueller <spitz at lyx.org>
> Date:   Wed Nov 20 11:48:18 2019 +0100
>
>     Re-fix #11146 with recent LaTeX

Fine for stable if needed.

Riki