bug#81611: 31.0.90; show-paren-mode reports false mismatch

> Cc: [email protected]
> Date: Wed, 12 Aug 2026 15:50:24 -0400
> From: Stefan Monnier via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <[email protected]>
> 
> > Suggested fix: Before narrowing, check syntax-ppss at the cutoff; if it
> > is inside a string or comment, don't cut there -- but snap forward (or
> > backward) to a position outside strings/comments.
> 
> +1
> 
> And I believe the "snap forward" can be done by `parse-partial-sexp` with
> COMMENTSTOP arg of `syntax-table`.  The snap backward is simpler (just
> jump to (nth 8 ppss)), but could jump very far back if the
> string/comment is very long.

Wouldn't syntax-ppss run the risk of going far back?