Running multiple of instances of Manager

The reason I've prevented you from running multiple instances of Manager is simple: you could run into weird situations and issues (e.g. files already in use by another instance), so it's best avoided entirely. Besides, why would you need to run multiple instances anyway?

Since version 1.3.0, if you try to start a second instance of Manager, the window of the existing instance will be restored from the tray icon if necessary and focused, then the new instance will close. Additionally, any command line arguments you passed to the new instance, will be forwarded to the existing one. So now when you try to start a VM from a desktop shortcut when Manager is already running, you'll see it start rightaway, instead of the error dialog from before.