[LyX/master] Fix wrong \inputencoding after a command paragraph closes

[Udi Fogiel]

commit bf8fd567d4c33fba5136730e96fe39e1cd63efeb
Author: Udi Fogiel <ufogiel at lyx.org>
Date:   Thu Jul 9 18:29:33 2026 +0300

    Fix wrong \inputencoding after a command paragraph closes
    
    for example a title that contains an input encoding switch.
    Fixes #12927.
---
 src/output_latex.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/output_latex.cpp b/src/output_latex.cpp
index 2e571df1ce..94ed36b3f3 100644
--- a/src/output_latex.cpp
+++ b/src/output_latex.cpp
@@ -1158,6 +1158,13 @@ void TeXOnePar(Buffer const & buf,
 		}
 	}
 
+	// Remember the encoding in effect before this paragraph, so that it can be
+	// restored once a command argument (e.g. \title{...}) that brace-groups its
+	// content closes. This must be captured before the look-ahead switch below,
+	// which may move a later encoding change to the beginning of the paragraph
+	// and would otherwise corrupt the value to restore to.
+	Encoding const * const orig_encoding = runparams.encoding;
+
 	// Switch file encoding if necessary; no need to do this for "auto-legacy-plain"
 	// encoding, since this only affects the position of the outputted
 	// \inputencoding command; the encoding switch will occur when necessary
@@ -1223,7 +1230,7 @@ void TeXOnePar(Buffer const & buf,
 	runparams.moving_arg |= style.needprotect;
 	if (style.needmboxprotect)
 		++runparams.inulemcmd;
-	Encoding const * const prev_encoding = runparams.encoding;
+	Encoding const * const prev_encoding = orig_encoding;
 
 	bool const useSetSpace = bparams.documentClass().provides("SetSpace");
 	if (par.allowParagraphCustomization()) {