diff --git a/src/frontends/qt4/GuiDelimiter.cpp b/src/frontends/qt4/GuiDelimiter.cpp
index 2ff733554f..2ddcfa6712 100644
--- a/src/frontends/qt4/GuiDelimiter.cpp
+++ b/src/frontends/qt4/GuiDelimiter.cpp
@@ -296,6 +296,9 @@ void GuiDelimiter::on_sizeCO_activated(int index)
 
 void GuiDelimiter::on_leftLW_itemActivated(QListWidgetItem *)
 {
+	if (!matchCB->isChecked())
+		// do not apply
+		return;
 	on_insertPB_clicked();
 	accept();
 }
@@ -303,6 +306,9 @@ void GuiDelimiter::on_leftLW_itemActivated(QListWidgetItem *)
 
 void GuiDelimiter::on_rightLW_itemActivated(QListWidgetItem *)
 {
+	if (!matchCB->isChecked())
+		// do not apply
+		return;
 	on_insertPB_clicked();
 	accept();
 }