diff --git a/UI/window-basic-main.cpp b/UI/window-basic-main.cpp
index f2126f10d..946dd5d08 100644
--- a/UI/window-basic-main.cpp
+++ b/UI/window-basic-main.cpp
@@ -5757,7 +5757,12 @@ void OBSBasic::on_actionCopySource_triggered()
 	copyVisible = obs_sceneitem_visible(item);
 
 	ui->actionPasteRef->setEnabled(true);
-	ui->actionPasteDup->setEnabled(true);
+
+	uint32_t output_flags = obs_source_get_output_flags(source);
+	if ((output_flags & OBS_SOURCE_DO_NOT_DUPLICATE) == 0)
+		ui->actionPasteDup->setEnabled(true);
+	else
+		ui->actionPasteDup->setEnabled(false);
 }
 
 void OBSBasic::on_actionPasteRef_triggered()