Thanks for your help. At the moment I have in my init.el  (in fact my user.el because I am using scimax with -q -l options):

(require 'ox-latex)
(setq org-src-fontify-natively t)
(setq org-highlight-latex-and-related '(latex))
(setq org-highlight-latex-and-related '(latex script entities))

But nothing works for highlighting latex.

Best wishes,


Jo.

2018-05-09 13:21 GMT+02:00 Eric S Fraga <esflists@gmail.com>:
On Wednesday,  9 May 2018 at 11:59, Nicolas Goaziou wrote:
> Eric S Fraga <esflists@gmail.com> writes:
>
>> Okay.  But I have this variable set, to (latex), and it does
>> nothing.  The regex remains nil.  Is there some other configuration
>> setting that we have to set to get LaTeX snippets etc. highlighted?
>
> You may need to reload Org mode in the current buffer.

But I have this set from the start and also tried with
custom-set-variable... and I have tried reloading org.  All to no
avail.

The highlighting works if I try emacs -Q so obviously something else is
affecting this setting.  Ummmm time to dive into my customization of
org.  Any hints as to what could be affecting the actual highlighting
would be welcome, of course!

thanks,
eric

--
Eric S Fraga via Emacs 27.0.50, Org release_9.1.11-620-ga548e4