SearchHighlight.vim

func! SearchHighlight(timer) abort
  if !v:hlsearch || mode() isnot 'n'
    return
  else
    let cmd="\<c-\>\<c-n>:let v:hlsearch=0\<cr>\<c-l>"
    sil call feedkeys(cmd, 'n')
  endif
endfu

func! s:TimerHighlight() abort
  if exists("g:search_timer_id")
    return
  else
    let g:search_timer_id = timer_start(7000, 'SearchHighlight', {'repeat': -1})                                                                                                                                                      endif
endfunction

func! s:SearchHighlightInit() abort
  if exists("g:search_timer_id")
    sil! call timer_stop(g:search_timer_id)
    unlet! g:search_timer_id
  endif
  augroup SearchHighlight
    au!
    au CursorMoved * call s:TimerHighlight()
  augroup end
endfu

:com! SearchHighlightTimer :call s:SearchHighlightInit()