bug#58005: 13.1.4; Can't work with indirect buffers

[Paul Nelson]

> A brief testing didn't show fatal behavior. Here are two notes I noticed:
> 1. In indirect buffer, preview-latex doesn't work. All preview images
>    appear in the base buffer.
> 2. TeX Fold mode works independently in indirect and base buffers.
>
> I suppose there will be dissatisfied users about item 1. Do you have any
> good idea about it?
> Item 2 can be a useful feature rather than a shortcoming, whereas some
> users want to inherit the folded appearance when they clone a buffer.
>
> Maybe we should regard these points as feature and announce them as
> "known limitations".
>

I'd be happy to take a quick look at this if I could see the patch in
question.  (I've been using indirect buffers with my local copy of
preview-latex for years.  The key point, if I recall correctly, was to
trick "preview-region" into thinking it's being called in "non-file"
mode, so that "<none>" gets passed along to preview-parse-messages and
hence the previews are placed (correctly) in the command buffer rather
than (incorrectly, as you've observed here) in the buffer with the
same name as the master file.)