Sometimes I want to make a screenshot and found that if I do that on a 4k screen, then the screenshot is quite clear (and is in a high resolution).
So I can do this when my Macbook Pro is connected to a 4k display. But let's say if I am on a trip, how do I make the Macbook Pro show or think it is showing in 4k? I think this is possible even when we don't install any driver or software, because we can plug in a 4k display and choose "mirror the 2 displays" and the Macbook Pro native screen will pretend that it is a 4k screen, and any screen capture there will be in 4k resolution.
So the question is, if I temporarily don't have a 4k display, say on a business trip, how do I tell the Mac to show the native screen in 4k or even 5k?