Support for the often confusing X11 clipboard - aka CLIPBOARD/PRIMARY - predominantly depends on the toolkit (think GTK, Qt) your particular application uses. I

Support for the often confusing X11 clipboard - aka CLIPBOARD/PRIMARY - predominantly depends on the toolkit (think GTK, Qt) your particular application uses. I'm very fond of Mark=Copy and Ctrl+Insert/MiddleClick=Paste, and to teach all the (modern) applications I also use to honor my preferences, I have a clipboard manager installed. My choice is XFCE's `clipman`, but all the popular and big desktop environments offer their own, functionally at least equivalent application for the purpose: KDE has "klipper", for example, while GNOME probably sports an extension that does the job. There are more standalone implementations, too, that don't target a specific DE at all. Running one in your session allows to sync the toolkits' clipboards with X11's clipboard, which is what I choose to do - you only have one (history-enabled) clipboard that way, but it keeps the surprise effect ("Oh... I wasn't aware I was gonna paste _that_...") to a minimum, too :)