[LyX/master] add local language switch (file format change)

[Udi Fogiel]

On Monday, July 13th, 2026 at 12:07 AM, Kornel Benko <kornel at lyx.org> wrote:
> This breaks the adv-search for text in different languages.
> I have problems with
> \text???[...]{...}
> \begin{???}[] ... \end{???}
> All of sudden 'Find' has to memorise all languages and all variants (since 'find' is
> based on latex output).
> 
> Previously it was easier to handle \selectlanguage and \foreignlanguage :(

I'm not sure I quite understand. This commit does not add any new LaTeX code.
LyX already use \text???[...]{...} or \begin{???}[] ... \end{???}
with polyglossia.

That said I'm not familiar at all with the code for adv-search so...

Udi