[LyX/master] Fix #13318 (correct context menu in equations)

[Koji Yokota]

commit 5e4daba5b87ad858501d0a0e084345f5eaa05699
Author: Koji Yokota <yokota at lyx.org>
Date:   Sun Aug 16 13:43:14 2026 +0900

    Fix #13318 (correct context menu in equations)
---
 src/frontends/qt/GuiWorkArea.cpp | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/frontends/qt/GuiWorkArea.cpp b/src/frontends/qt/GuiWorkArea.cpp
index b4b4b7e401..d3f23901a2 100644
--- a/src/frontends/qt/GuiWorkArea.cpp
+++ b/src/frontends/qt/GuiWorkArea.cpp
@@ -753,25 +753,26 @@ void GuiWorkArea::contextMenuEvent(QContextMenuEvent * e)
 		// the menu name is set on mouse press
 		name = d->context_menu_name_;
 	else {
-		QPoint pos = e->pos();
 		Cursor const & cur = d->buffer_view_->cursor();
+		int x, y;
+		cur.getPos(x, y);
 		if (e->reason() == QContextMenuEvent::Keyboard && cur.inTexted()) {
 			// Do not access the context menu of math right in front of before
 			// the cursor. This does not work when the cursor is in text.
 			Inset * inset = cur.paragraph().getInset(cur.pos());
 			if (inset && inset->asInsetMath())
-				--pos.rx();
+				--x;
 			else if (cur.pos() > 0) {
 				inset = cur.paragraph().getInset(cur.pos() - 1);
 				if (inset)
-					++pos.rx();
+					++x;
 			}
 		}
 		if (e->reason() == QContextMenuEvent::Keyboard)
 			// Subtract the top margin, see #12811
-			pos.setY(pos.y() - d->buffer_view_->topMargin());
+			y -= d->buffer_view_->topMargin();
 
-		name = d->buffer_view_->contextMenu(pos.x(), pos.y());
+		name = d->buffer_view_->contextMenu(x, y);
 	}
 
 	if (name.empty()) {