Update main.js

Add window reopen procedure for macos

main.js

@@ -14,6 +14,11 @@ const createWindow = () => {
 // Call window instantiating function when the app is ready
 app.whenReady().then(() => {
     createWindow()
+
+    // Open a window if none are open (macos only)
+    app.on('activate', () => {
+        if (BrowserWindow.getAllWindows().length === 0) createWindow()
+    })
 })
 
 // Quit the app when all windows are closed (for windows and linux only)