This is yet another packaging of the Chromium hterm code that sends OSC 52 escape sequences to populate the terminal clipboard. There's nothing particularly special about this copy except for a new function that sends all yanked text to the terminal auto-magically. ¯_(ツ)_/¯
Use your favorite plugin manager to install it. I use junegunn/vim-plug.
Plug 'sykesm/vim-osc52'
If you want yank to send text to the terminal as well as the buffer, the following mappings can be used:
if !has("gui_running") && !empty($SSH_CLIENT)
nnoremap <silent> yy :<C-U>call YankToTerminalClipboard('yy')<CR>
nnoremap <silent> y :set operatorfunc=YankToTerminalClipboard<CR>g@
vnoremap <silent> y :<C-U>call YankToTerminalClipboard(visualmode(), 1)<CR>
endif
This is covered by the original BSD-style license from Chromium. It can be found in LICENSE.