[LyX/2.4.x] Fixup b29b3eb1: close <mtext> when quitting text mode

[Jean-Marc Lasgouttes]

commit 458ce0fdba19094f97b96b7747a2d7b82d4d7087
Author: Jean-Marc Lasgouttes <lasgouttes at lyx.org>
Date:   Tue Jul 23 22:02:50 2024 +0200

    Fixup b29b3eb1: close <mtext> when quitting text mode
    
    This fixes malformed documents on UserGuide export.
    
    Related to bug #13069.
    
    (cherry picked from commit 1385f0fddd0229770496b1e50b76782892032d18)
---
 src/mathed/MathStream.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/mathed/MathStream.cpp b/src/mathed/MathStream.cpp
index 2951aeeefd..665b3fcbf4 100644
--- a/src/mathed/MathStream.cpp
+++ b/src/mathed/MathStream.cpp
@@ -547,6 +547,7 @@ SetMode::SetMode(MathMLStream & ms, bool text)
 
 SetMode::~SetMode()
 {
+	ms_.beforeTag();
 	ms_.text_level_ = old_text_level_;
 }