Earlier quoted context omitted.
It’s a generic feature of X available in all desktop environments (essentially there’s two copy-paste mechanism which you can use independently). Much easier to use than manual C-c C-v, especially if you have a third mouse button also on your laptop.
And this is the problem. There is zero thought being given to different usage scenarios, and when it is, it's a chaotic solution that works some of the time. How do you middle-click-paste if you are on a trackpad with only two buttons, for example? I'm only picking on this to illustrate the point: things are hacked together at almost every level for a workstation. This is why "The Year of the Linux Desktop" never hap…
Tap twice and drag on the second tap to select.
Tap with three fingers to paste.
Don't use the buttons.