When in most foreground dialog windows the app's menu bar, the app's toolbar
controls & [usually] the Control/Right-Click (contextual) menus are
unavailable. However, the keyboard shortcut is universal to the OS. Yes, I
have no trouble with the Command+V keystroke here pasting into the Create
New Source dialog or the Edit Source dialog.
I'm not sure what you mean by "citation tool" ‹ there are several components
for working with Citations but none of them are known by that name.
Are you trying to paste directly to the Citations List in the Toolbox? Are
you trying to paste into the Citation Source Manager window? You cannot
paste directly into either of them.
HTH |:>)
Bob Jones
[MVP] Office:Mac