blubb.vim

command! Foo call fzf#run({
      \ 'source': map(getqflist(), 'bufname(v:val.bufnr).":".v:val.lnum.":".v:val.text'),
      \ 'sink': function('<sid>open')
      \ })

function! s:open(entry)
  let [file, linenr] = matchlist(a:entry, '\v([^:]*):([^:]*)')[1:2]
  execute 'edit +'.linenr file
endfunction

autocmd User Grepper Foo

" So we automatically call this if :Grepper finishes:
"   :Grepper! -noopen -query foo