Copy and paste on Ubuntu
On a Mac, if you press Command-C while not selecting anything, nothing happens. I didn't realize this was a behavior that had been designed and implemented by someone until I did the same on Ubuntu.
On Ubuntu, what happens when you press Ctrl-C while not selecting anything is two things:
I'm saying as if this is an Ubuntu problem. But I don't really know. It is most likely handled by Gnome alongside (in my case) X11 according to Reddit.
And you would think the clipboard is a solved problem since it was invented in 1973.