UI: Refresh multiview projector menu per click

UI/window-basic-main.cpp

@@ -1647,15 +1647,21 @@ void OBSBasic::OBSInit()
 
 	ui->viewMenu->addSeparator();
 
-	QMenu *multiviewProjectorMenu = new QMenu(QTStr("MultiviewProjector"));
-	AddProjectorMenuMonitors(multiviewProjectorMenu, this,
-			SLOT(OpenMultiviewProjector()));
+	multiviewProjectorMenu = new QMenu(QTStr("MultiviewProjector"));
 	ui->viewMenu->addMenu(multiviewProjectorMenu);
-
+	connect(ui->viewMenu->menuAction(), &QAction::hovered, this,
+			&OBSBasic::UpdateMultiviewProjectorMenu);
 	ui->viewMenu->addAction(QTStr("MultiviewWindowed"),
 			this, SLOT(OpenMultiviewWindow()));
 }
 
+void OBSBasic::UpdateMultiviewProjectorMenu()
+{
+	multiviewProjectorMenu->clear();
+	AddProjectorMenuMonitors(multiviewProjectorMenu, this,
+			SLOT(OpenMultiviewProjector()));
+}
+
 void OBSBasic::InitHotkeys()
 {
 	ProfileScope("OBSBasic::InitHotkeys");

UI/window-basic-main.hpp

@@ -186,6 +186,9 @@ private:
 	QPointer<QAction>         exit;
 	QPointer<QMenu>           trayMenu;
 
+	QPointer<QMenu> multiviewProjectorMenu;
+	void          UpdateMultiviewProjectorMenu();
+
 	void          DrawBackdrop(float cx, float cy);
 
 	void          SetupEncoders();