Modifying the <leader>gh command to copy to clipboard is working on Fedora.

[ybettan]

Using let g:gh_open_command = 'fn() { echo "$@" | pbcopy; }; fn ' as mentioned in the README didn't work for me but using let g:gh_open_command = 'fn() { echo "$@" | xclip; }; fn ' instead did the trick.