Preference for focus existing app or open new

[diogox]

Create preference for focusing an existing instance of an app when trying to open one, or create a new instance regardless?

[diogox]

Not sure if this makes sense: On the one hand, apps like spotify, for example, shouldn't have more than one instance open at any given time; on the other hand, when I want to open firefox I probably want a new tab or window... Maybe I should leave this up to the command inside the app's ".desktop" file...