diff --git a/.travis.yml b/.travis.yml
index 5fc0240..028ca78 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ env:
     - PATH=$DEPS/bin:$PATH
 matrix:
   include:
-    - env: ENV=vim72
+    - env: ENV=vim74
       rvm: 1.8.7
       addons: { apt: { packages: [vim-nox] } }
     - env: ENV=python
@@ -26,7 +26,7 @@ install: |
   git config --global user.email "you@example.com"
   git config --global user.name "Your Name"
 
-  if [ "$ENV" == "vim72" ]; then
+  if [ "$ENV" == "vim74" ]; then
     mkdir -p ${DEPS}/bin
     ln -s /usr/bin/vim.nox ${DEPS}/bin/vim
     return
diff --git a/plug.vim b/plug.vim
index 2475fb4..f7c4444 100644
--- a/plug.vim
+++ b/plug.vim
@@ -96,7 +96,7 @@ let s:plug_src = 'https://github.com/junegunn/vim-plug.git'
 let s:plug_tab = get(s:, 'plug_tab', -1)
 let s:plug_buf = get(s:, 'plug_buf', -1)
 let s:mac_gui = has('gui_macvim') && has('gui_running')
-let s:is_win = has('win32') || has('win64')
+let s:is_win = has('win32')
 let s:nvim = has('nvim-0.2') || (has('nvim') && exists('*jobwait') && !s:is_win)
 let s:vim8 = has('patch-8.0.0039') && exists('*job_start')
 let s:me = resolve(expand('<sfile>:p'))
@@ -194,6 +194,14 @@ function! s:ask_no_interrupt(...)
   endtry
 endfunction
 
+function! s:lazy(plug, opt)
+  return has_key(a:plug, a:opt) &&
+        \ (empty(s:to_a(a:plug[a:opt]))         ||
+        \  !isdirectory(a:plug.dir)             ||
+        \  len(s:glob(s:rtp(a:plug), 'plugin')) ||
+        \  len(s:glob(s:rtp(a:plug), 'after/plugin')))
+endfunction
+
 function! plug#end()
   if !exists('g:plugs')
     return s:err('Call plug#begin() first')
@@ -215,7 +223,7 @@ function! plug#end()
       continue
     endif
     let plug = g:plugs[name]
-    if get(s:loaded, name, 0) || !has_key(plug, 'on') && !has_key(plug, 'for')
+    if get(s:loaded, name, 0) || !s:lazy(plug, 'on') && !s:lazy(plug, 'for')
       let s:loaded[name] = 1
       continue
     endif
@@ -811,6 +819,9 @@ function! s:prepare(...)
     execute 'silent! unmap <buffer>' k
   endfor
   setlocal buftype=nofile bufhidden=wipe nobuflisted nolist noswapfile nowrap cursorline modifiable nospell
+  if exists('+colorcolumn')
+    setlocal colorcolumn=
+  endif
   setf vim-plug
   if exists('g:syntax_on')
     call s:syntax()
@@ -1056,6 +1067,8 @@ function! s:update_impl(pull, force, args) abort
     let s:clone_opt .= ' -c core.eol=lf -c core.autocrlf=input'
   endif
 
+  let s:submodule_opt = s:git_version_requirement(2, 8) ? ' --jobs='.threads : ''
+
   " Python version requirement (>= 2.7)
   if python && !has('python3') && !ruby && !use_job && s:update.threads > 1
     redir => pyv
@@ -1147,7 +1160,7 @@ function! s:update_finish()
       if !v:shell_error && filereadable(spec.dir.'/.gitmodules') &&
             \ (s:update.force || has_key(s:update.new, name) || s:is_updated(spec.dir))
         call s:log4(name, 'Updating submodules. This may take a while.')
-        let out .= s:bang('git submodule update --init --recursive 2>&1', spec.dir)
+        let out .= s:bang('git submodule update --init --recursive'.s:submodule_opt.' 2>&1', spec.dir)
       endif
       let msg = s:format_message(v:shell_error ? 'x': '-', name, out)
       if v:shell_error
@@ -1366,7 +1379,7 @@ while 1 " Without TCO, Vim stack is bound to explode
 
   let name = keys(s:update.todo)[0]
   let spec = remove(s:update.todo, name)
-  let new  = !isdirectory(spec.dir)
+  let new  = empty(globpath(spec.dir, '.git', 1))
 
   call s:log(new ? '+' : '*', name, pull ? 'Updating ...' : 'Installing ...')
   redraw
@@ -2259,7 +2272,7 @@ function! s:upgrade()
   let new = tmp . '/plug.vim'
 
   try
-    let out = s:system(printf('git clone --depth 1 %s %s', s:plug_src, tmp))
+    let out = s:system(printf('git clone --depth 1 %s %s', s:shellesc(s:plug_src), s:shellesc(tmp)))
     if v:shell_error
       return s:err('Error upgrading vim-plug: '. out)
     endif
@@ -2455,7 +2468,11 @@ function! s:diff()
     call s:append_ul(2, origin ? 'Pending updates:' : 'Last update:')
     for [k, v] in plugs
       let range = origin ? '..origin/'.v.branch : 'HEAD@{1}..'
-      let diff = s:system_chomp('git log --graph --color=never '.join(map(['--pretty=format:%x01%h%x01%d%x01%s%x01%cr', range], 's:shellesc(v:val)')), v.dir)
+      let cmd = 'git log --graph --color=never '.join(map(['--pretty=format:%x01%h%x01%d%x01%s%x01%cr', range], 's:shellesc(v:val)'))
+      if has_key(v, 'rtp')
+        let cmd .= ' -- '.s:shellesc(v.rtp)
+      endif
+      let diff = s:system_chomp(cmd, v.dir)
       if !empty(diff)
         let ref = has_key(v, 'tag') ? (' (tag: '.v.tag.')') : has_key(v, 'commit') ? (' '.v.commit) : ''
         call append(5, extend(['', '- '.k.':'.ref], map(s:lines(diff), 's:format_git_log(v:val)')))
@@ -2474,8 +2491,13 @@ function! s:diff()
         \ . (cnts[1] ? printf(' %d plugin(s) have pending updates.', cnts[1]) : ''))
 
   if cnts[0] || cnts[1]
-    nnoremap <silent> <buffer> <cr> :silent! call <SID>preview_commit()<cr>
-    nnoremap <silent> <buffer> o    :silent! call <SID>preview_commit()<cr>
+    nnoremap <silent> <buffer> <plug>(plug-preview) :silent! call <SID>preview_commit()<cr>
+    if empty(maparg("\<cr>", 'n'))
+      nmap <buffer> <cr> <plug>(plug-preview)
+    endif
+    if empty(maparg('o', 'n'))
+      nmap <buffer> o <plug>(plug-preview)
+    endif
   endif
   if cnts[0]
     nnoremap <silent> <buffer> X :call <SID>revert()<cr>
diff --git a/test/regressions.vader b/test/regressions.vader
index dd2a6a2..40f6d4b 100644
--- a/test/regressions.vader
+++ b/test/regressions.vader
@@ -41,6 +41,7 @@ Execute (#130 Proper cleanup of on-demand loading triggers):
   Plug 'junegunn/vim-emoji', { 'on':  ['EmojiCommand', 'EmojiCommand2', '<Plug>(EmojiMapping)'] }
   call plug#end()
   PlugInstall | q
+  call mkdir(g:plugs['vim-emoji'].dir.'/after/plugin', 'p')
 
   Assert exists(':EmojiCommand'), 'EmojiCommand not defined'
   Assert exists(':EmojiCommand2'), 'EmojiCommand2 not defined'
diff --git a/test/run b/test/run
index 92efc3b..2ddfd7e 100755
--- a/test/run
+++ b/test/run
@@ -91,7 +91,7 @@ DOC
   echo "let g:plug_config_vader_test = 1" > "$TEMP/configs/yyy.vim"
 
   rm -rf "$PLUG_FIXTURES/ftplugin-msg"
-  mkdir -p "$PLUG_FIXTURES/ftplugin-msg/ftplugin"
+  mkdir -p "$PLUG_FIXTURES"/ftplugin-msg/{plugin,ftplugin}
   echo "echomsg 'ftplugin-c'" > "$PLUG_FIXTURES/ftplugin-msg/ftplugin/c.vim"
   echo "echomsg 'ftplugin-java'" > "$PLUG_FIXTURES/ftplugin-msg/ftplugin/java.vim"
 
diff --git a/test/workflow.vader b/test/workflow.vader
index 269a884..5275bf2 100644
--- a/test/workflow.vader
+++ b/test/workflow.vader
@@ -370,8 +370,15 @@ Execute (New commits on remote, PlugUpdate, then PlugDiff):
   AssertEqual 1, &previewwindow
   AssertEqual 'git', &filetype
 
-  " Back to plug window
-  wincmd p
+  " Close preview window
+  pclose
+
+  " Open and go to preview window with a custom mapping
+  nmap <buffer> <c-o> <plug>(plug-preview)<c-w>P
+  execute "normal \<c-o>"
+  AssertEqual 1, &previewwindow, 'Should be on preview window'
+  normal q
+  AssertEqual 0, &previewwindow, 'Should not be on preview window'
 
   " ]] motion
   execute 'normal $]]'
@@ -530,6 +537,51 @@ Execute (PlugDiff):
   Assert !empty(mapcheck("\<cr>"))
   q
 
+Execute (Do not show diff for commits outside of rtp):
+  call plug#begin()
+  call plug#end()
+  PlugClean!
+
+  call plug#begin()
+  Plug 'file://'.expand('$PLUG_FIXTURES').'/xxx'
+  Plug 'file://'.expand('$PLUG_FIXTURES').'/yyy', { 'rtp': 'rtp' }
+  call plug#end()
+  PlugInstall
+  Log getline(1, '$')
+
+  call system('cd "$PLUG_FIXTURES/xxx" && git commit --allow-empty -m update-xxx && git tag -f xxx')
+  call system('cd "$PLUG_FIXTURES/yyy" && git commit --allow-empty -m update-yyy && git tag -f yyy')
+
+  let g:plugs.yyy.tag = 'yyy'
+  PlugUpdate
+  Log getline(1, '$')
+
+  PlugDiff
+  " 1 plugin(s) updated.
+  " [==]
+  "
+  " Last update:
+  " ------------
+  "
+  " - xxx:
+  "   * 7faa9b2 update-xxx (0 seconds ago)
+  "
+  " Pending updates:
+  " ----------------
+  "
+  " N/A
+  "
+  Log getline(1, '$')
+  AssertEqual 14, line('$')
+  AssertEqual '1 plugin(s) updated.', getline(1)
+  AssertEqual '[==]', getline(2)
+  AssertEqual 'Last update:', getline(4)
+  AssertEqual '- xxx:', getline(7)
+  Assert !empty(mapcheck('o'))
+  Assert !empty(mapcheck('X'))
+  Assert !empty(mapcheck("\<cr>"))
+  q
+
 **********************************************************************
 ~ On-demand loading / Partial installation/update ~
 **********************************************************************
@@ -1504,7 +1556,7 @@ Execute (Commit hash support):
   Log getline(1, '$')
   AssertEqual 'x goyo.vim:', getline(5)
   AssertEqual '    fatal: invalid reference: ffffffff', getline(6)
-  AssertEqual 0, stridx(getline(7), '- vim-emoji: HEAD is now at 9db7fcf...')
+  AssertEqual 0, stridx(getline(7), '- vim-emoji: HEAD is now at 9db7fcf')
 
   let hash = system(printf('cd %s && git rev-parse HEAD', g:plugs['vim-emoji'].dir))[:-2]
   AssertEqual '9db7fcfee0d90dafdbcb7a32090c0a9085eb054a', hash
@@ -1674,3 +1726,15 @@ Execute (PlugConfig shall load config automatically):
   redir => out
   AssertEqual 1, exists('g:plug_config_vader_test'), 'Variable has not been set by config'
   redir END
+
+Execute (#766 - Allow cloning into an empty directory):
+  let d = '/tmp/vim-plug-test/goyo-already'
+  call system('rm -rf ' . d)
+  call mkdir(d)
+  call plug#begin()
+  Plug 'junegunn/goyo.vim', { 'dir': d }
+  call plug#end()
+  PlugInstall
+  AssertExpect! '[=]', 1
+  q
+  unlet d