I attach the patch here.

However, I have two questions.
First, I am not certain that I set up the repository correctly, because when I run "make test" it generates 55 unexpected failures. This without making any changes.
(The patch submitted here does not generate any new failures.)

Second, the existing comment at the patch becomes slightly out of date with the change.
In fact, I propose that it might be good to update the docstring for `org-src-fontify-natively' to explicitly state that it enable fontification for src, example, and export blocks.
If that is agreed on, I am happy to submit a further patch.
Thanks,
Ben

On Mon, Sep 16, 2024 at 11:27 PM Benjamin McMillan <mcmillanbb@gmail.com> wrote:
Ok, I am happy to submit a patch. It would be my first, so I will have to find time to make the commit properly.

On Wed, Sep 11, 2024 at 1:59 AM Ihor Radchenko <yantar92@posteo.net> wrote:
Benjamin McMillan <mcmillanbb@gmail.com> writes:

> At some point in the last few months, org mode stopped fontifying my
> latex export blocks. However, an older version of emacs on my computer
> still does fontify.
> (The difference is seen even opening emacs with the -q flag)
> It seems that there was a change to the function
> org-fontify-meta-lines-and-blocks-1 in org.el, specifically at the
> conditional that checks org-src-fontify-natively.
> As the comment there explains, the intention is to only fontify src
> blocks, but I don't see any option exposed to enable fontififcation of
> export blocks, which is a fairly crucial feature to my workflow.
>
> I think fontification of export blocks should follow that of src blocks,
> or a separate option should be made. (Or, I may be missing some already
> existing solution!)
>
> For what it is worth, I can get the desired behavior by modifying the
> code mentioned above to include "export", as in the following:
> (and org-src-fontify-natively
>     ;; Technically, according to
>     ;; `org-src-fontify-natively' docstring, we should
>     ;; only fontify src blocks.  However, it is common
>     ;; to use undocumented fontification of example
>     ;; blocks with undocumented language specifier.
>     ;; Keep this undocumented feature for user
>     ;; convenience.
>     (member block-type '("src" "example" "export")))

Since we already do it for example blocks, I see not why we should not
for export blocks.

Would you be interested to submit a patch with your modification?
See https://orgmode.org/worg/org-contribute.html#first-patch

--
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
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