The standard Cmd-C to copy, Cmd-V to paste, plus Ctrl-C to copy, Ctrl-V to paste, can do that. Usually. Occasionally there's a bug which makes it not work correctly.
Manga @ Triumph
"Meanwhile In The Halls Of Titan"...Titan Network Working To Save City Of Heroes
Save Paragon City! Efforts Coordination
Is there a way to do this in the Mac client? To, for instance, copy a URL? I couldn't find a way, but am prepared to believe I'm missing it.