Copy on select, who needs a keyboard ;)
PRIMARY: Copy by select, paste with middle click or shift-insert.
CLIPBOARD: Copy with explicit copy action, paste with explicit paste action (mostly ctrl-c/ctrl-v, except in terminals/vim)
I'm not sure if this is carried over into Wayland. I've seen some Mac terminals offer copy on select and there it does clobber the clipboard, unlike on Linux.
Vim exposes these as the * (PRIMARY) and " (CLIPBOARD) buffers