I’d imagine a berry of some sort. There could be a berry we still eat that pre-humans also ate. Wouldn’t surprise me.

Ah crap, yeah, I forgot about that, you’re right.

Keep in mind both options require enabling remote control from Windows settings. It’s off by default if I recall right.

If you have another windows pc, you can use the built-in remote desktop. Or, from Linux you can install a Microsoft rdp compatible client like remmina. (Edit: If using Windows Pro on the target machine, for either of these options)

I don’t personally know of any but in a similar vein there are some stone monuments intended to convey information after an apocalypse like the Georgia Guidestones or the nuclear waste site warning stones. GitHub put a snapshot of all active code repositories from 2020 in arctic permafrost, and there is the arctic seed vault for preserving plant species.