diff --git a/autoload/airline/util.vim b/autoload/airline/util.vim
index 71c42fcd..6b975990 100644
--- a/autoload/airline/util.vim
+++ b/autoload/airline/util.vim
@@ -1,4 +1,4 @@
-" MIT License. Copyright (c) 2013-2026 Bailey Ling, Christian Brabandt et al.
+" MIT License. Copyright (c) 2013-2021 Bailey Ling Christian Brabandt et al.
 " vim: et ts=2 sts=2 sw=2
 
 scriptencoding utf-8
@@ -13,235 +13,6 @@ let s:has_strchars = exists('*strchars')
 let s:has_strcharpart = exists('*strcharpart')
 let s:focusgained_ignore_time = 0
 
-" TODO: Try to cache winwidth(0) function
-" e.g. store winwidth per window and access that, only update it, if the size
-" actually changed.
-function! airline#util#winwidth(...) abort
-  let nr = get(a:000, 0, 0)
-  " When statusline is on top, or using global statusline for Neovim
-  " always return the number of columns
-  if get(g:, 'airline_statusline_ontop', 0) || &laststatus > 2
-    return &columns
-  else
-    return winwidth(nr)
-  endif
-endfunction
-
-function! airline#util#shorten(text, winwidth, minwidth, ...)
-  if airline#util#winwidth() < a:winwidth && len(split(a:text, '\zs')) > a:minwidth
-    if get(a:000, 0, 0)
-      " shorten from tail
-      return '…'.matchstr(a:text, '.\{'.a:minwidth.'}$')
-    else
-      " shorten from beginning of string
-      return matchstr(a:text, '^.\{'.a:minwidth.'}').'…'
-    endif
-  else
-    return a:text
-  endif
-endfunction
-
-function! airline#util#wrap(text, minwidth)
-  if a:minwidth > 0 && airline#util#winwidth() < a:minwidth
-    return ''
-  endif
-  return a:text
-endfunction
-
-function! airline#util#append(text, minwidth)
-  if a:minwidth > 0 && airline#util#winwidth() < a:minwidth
-    return ''
-  endif
-  let prefix = s:spc == "\ua0" ? s:spc : s:spc.s:spc
-  return empty(a:text) ? '' : prefix.g:airline_left_alt_sep.s:spc.a:text
-endfunction
-
-function! airline#util#warning(msg)
-  echohl WarningMsg
-  echomsg "airline: ".a:msg
-  echohl Normal
-endfunction
-
-function! airline#util#prepend(text, minwidth)
-  if a:minwidth > 0 && airline#util#winwidth() < a:minwidth
-    return ''
-  endif
-  return empty(a:text) ? '' : a:text.s:spc.g:airline_right_alt_sep.s:spc
-endfunction
-
-if v:version >= 704
-  function! airline#util#getbufvar(bufnr, key, def)
-    return getbufvar(a:bufnr, a:key, a:def)
-  endfunction
-else
-  function! airline#util#getbufvar(bufnr, key, def)
-    let bufvals = getbufvar(a:bufnr, '')
-    return get(bufvals, a:key, a:def)
-  endfunction
-endif
-
-if v:version >= 704
-  function! airline#util#getwinvar(winnr, key, def)
-    return getwinvar(a:winnr, a:key, a:def)
-  endfunction
-else
-  function! airline#util#getwinvar(winnr, key, def)
-    let winvals = getwinvar(a:winnr, '')
-    return get(winvals, a:key, a:def)
-  endfunction
-endif
-
-if v:version >= 704
-  function! airline#util#exec_funcrefs(list, ...)
-    for Fn in a:list
-      let code = call(Fn, a:000)
-      if code != 0
-        return code
-      endif
-    endfor
-    return 0
-  endfunction
-else
-  function! airline#util#exec_funcrefs(list, ...)
-    " for 7.2; we cannot iterate the list, hence why we use range()
-    " for 7.3-[97, 328]; we cannot reuse the variable, hence the {}
-    for i in range(0, len(a:list) - 1)
-      let Fn{i} = a:list[i]
-      let code = call(Fn{i}, a:000)
-      if code != 0
-        return code
-      endif
-    endfor
-    return 0
-  endfunction
-endif
-
-" Compatibility wrapper for strchars, in case this vim version does not
-" have it natively
-function! airline#util#strchars(str)
-  if s:has_strchars
-    return strchars(a:str)
-  else
-    return strlen(substitute(a:str, '.', 'a', 'g'))
-  endif
-endfunction
-
-function! airline#util#strcharpart(...)
-  if s:has_strcharpart
-    return call('strcharpart',  a:000)
-  else
-    " does not handle multibyte chars :(
-    return a:1[(a:2):(a:3)]
-  endif
-endfunction
-
-function! airline#util#ignore_buf(name)
-  let pat = '\c\v'. get(g:, 'airline#ignore_bufadd_pat', '').
-        \ get(g:, 'airline#extensions#tabline#ignore_bufadd_pat',
-        \ '!|defx|gundo|nerd_tree|startify|tagbar|term://|undotree|vimfiler')
-  return match(a:name, pat) > -1
-endfunction
-
-function! airline#util#has_fugitive()
-  if !exists("s:has_fugitive")
-    let s:has_fugitive = exists('*FugitiveHead')
-  endif
-  return s:has_fugitive
-endfunction
-
-function! airline#util#has_zhihu()
-  if !has('nvim')
-    return 0
-  endif
-  try
-    call v:lua.require'zhihu'.setup()
-  catch
-    return 0
-  endtry
-  return 1
-endfunction
-
-function! airline#util#has_gina()
-  if !exists("s:has_gina")
-    let s:has_gina = (exists(':Gina') && v:version >= 800)
-  endif
-  return s:has_gina
-endfunction
-
-
-function! airline#util#has_lawrencium()
-  if !exists("s:has_lawrencium")
-    let s:has_lawrencium  = exists('*lawrencium#statusline')
-  endif
-  return s:has_lawrencium
-endfunction
-
-function! airline#util#has_vcscommand()
-  if !exists("s:has_vcscommand")
-    let s:has_vcscommand = exists('*VCSCommandGetStatusLine')
-  endif
-  return get(g:, 'airline#extensions#branch#use_vcscommand', 0) && s:has_vcscommand
-endfunction
-
-function! airline#util#has_custom_scm()
-  return !empty(get(g:, 'airline#extensions#branch#custom_head', ''))
-endfunction
-
-function! airline#util#doautocmd(event)
-  if !exists('#airline') && a:event !=? 'AirlineToggledOff'
-    " airline disabled
-    return
-  endif
-  try
-    exe printf("silent doautocmd %s User %s", s:nomodeline, a:event)
-  catch /^Vim\%((\a\+)\)\=:E48:/
-    " Catch: Sandbox mode
-    " no-op
-  endtry
-endfunction
-
-function! airline#util#themes(match)
-  let files = split(globpath(&rtp, 'autoload/airline/themes/'.a:match.'*.vim', 1), "\n")
-  return sort(map(files, 'fnamemodify(v:val, ":t:r")') + ('random' =~ a:match ? ['random'] : []))
-endfunction
-
-function! airline#util#stl_disabled(winnr)
-  " setting the statusline is disabled,
-  " either globally, per window, or per buffer
-  " w:airline_disabled is deprecated!
-  return get(g:, 'airline_disable_statusline', 0) ||
-   \ airline#util#getwinvar(a:winnr, 'airline_disable_statusline', 0) ||
-   \ airline#util#getwinvar(a:winnr, 'airline_disabled', 0) ||
-   \ airline#util#getbufvar(winbufnr(a:winnr), 'airline_disable_statusline', 0)
-endfunction
-
-function! airline#util#ignore_next_focusgain()
-  if has('win32')
-    " Setup an ignore for platforms that trigger FocusLost on calls to
-    " system(). macvim (gui and terminal) and Linux terminal vim do not.
-    let s:focusgained_ignore_time = localtime()
-  endif
-endfunction
-
-function! airline#util#is_popup_window(winnr)
-   " Keep the statusline active if it's a popup window
-   if exists('*win_gettype')
-     return win_gettype(a:winnr) ==# 'popup' || win_gettype(a:winnr) ==# 'autocmd'
-   else
-      return airline#util#getwinvar(a:winnr, '&buftype', '') ==# 'popup'
-  endif
-endfunction
-
-function! airline#util#try_focusgained()
-  " Ignore lasts for at most one second and is cleared on the first
-  " focusgained. We use ignore to prevent system() calls from triggering
-  " FocusGained (which occurs 100% on win32 and seem to sometimes occur under
-  " tmux).
-  let dt = localtime() - s:focusgained_ignore_time
-  let s:focusgained_ignore_time = 0
-  return dt >= 1
-endfunction
-
 function! airline#util#has_vim9_script()
   " Returns true, if Vim is new enough to understand vim9 script
   return (exists(":def") &&
@@ -250,9 +21,435 @@ function! airline#util#has_vim9_script()
     \ get(g:, "airline_experimental", 0))
 endfunction
 
-function! airline#util#has_multiline()
-  " Returns true, if Vim supports multiline statusline (Vim 9.2.0083)
-  return (exists("+statuslineopt") &&
-    \ get(g:, "airline_multiline", 0))
-endfunction
+if !exists(":def") || !airline#util#has_vim9_script()
+  " TODO: Try to cache winwidth(0) function
+  " e.g. store winwidth per window and access that, only update it, if the size
+  " actually changed.
+  function! airline#util#winwidth(...) abort
+    let nr = get(a:000, 0, 0)
+    " When statusline is on top, or using global statusline for Neovim
+    " always return the number of columns
+    if get(g:, 'airline_statusline_ontop', 0) || &laststatus > 2
+      return &columns
+    else
+      return winwidth(nr)
+    endif
+  endfunction
 
+  function! airline#util#shorten(text, winwidth, minwidth, ...)
+    if airline#util#winwidth() < a:winwidth && len(split(a:text, '\zs')) > a:minwidth
+      if get(a:000, 0, 0)
+        " shorten from tail
+        return '…'.matchstr(a:text, '.\{'.a:minwidth.'}$')
+      else
+        " shorten from beginning of string
+        return matchstr(a:text, '^.\{'.a:minwidth.'}').'…'
+      endif
+    else
+      return a:text
+    endif
+  endfunction
+
+  function! airline#util#wrap(text, minwidth)
+    if a:minwidth > 0 && airline#util#winwidth() < a:minwidth
+      return ''
+    endif
+    return a:text
+  endfunction
+
+  function! airline#util#append(text, minwidth)
+    if a:minwidth > 0 && airline#util#winwidth() < a:minwidth
+      return ''
+    endif
+    let prefix = s:spc == "\ua0" ? s:spc : s:spc.s:spc
+    return empty(a:text) ? '' : prefix.g:airline_left_alt_sep.s:spc.a:text
+  endfunction
+
+  function! airline#util#warning(msg)
+    echohl WarningMsg
+    echomsg "airline: ".a:msg
+    echohl Normal
+  endfunction
+
+  function! airline#util#prepend(text, minwidth)
+    if a:minwidth > 0 && airline#util#winwidth() < a:minwidth
+      return ''
+    endif
+    return empty(a:text) ? '' : a:text.s:spc.g:airline_right_alt_sep.s:spc
+  endfunction
+
+  if v:version >= 704
+    function! airline#util#getbufvar(bufnr, key, def)
+      return getbufvar(a:bufnr, a:key, a:def)
+    endfunction
+  else
+    function! airline#util#getbufvar(bufnr, key, def)
+      let bufvals = getbufvar(a:bufnr, '')
+      return get(bufvals, a:key, a:def)
+    endfunction
+  endif
+
+  if v:version >= 704
+    function! airline#util#getwinvar(winnr, key, def)
+      return getwinvar(a:winnr, a:key, a:def)
+    endfunction
+  else
+    function! airline#util#getwinvar(winnr, key, def)
+      let winvals = getwinvar(a:winnr, '')
+      return get(winvals, a:key, a:def)
+    endfunction
+  endif
+
+  if v:version >= 704
+    function! airline#util#exec_funcrefs(list, ...)
+      for Fn in a:list
+        let code = call(Fn, a:000)
+        if code != 0
+          return code
+        endif
+      endfor
+      return 0
+    endfunction
+  else
+    function! airline#util#exec_funcrefs(list, ...)
+      " for 7.2; we cannot iterate the list, hence why we use range()
+      " for 7.3-[97, 328]; we cannot reuse the variable, hence the {}
+      for i in range(0, len(a:list) - 1)
+        let Fn{i} = a:list[i]
+        let code = call(Fn{i}, a:000)
+        if code != 0
+          return code
+        endif
+      endfor
+      return 0
+    endfunction
+  endif
+
+  " Compatibility wrapper for strchars, in case this vim version does not
+  " have it natively
+  function! airline#util#strchars(str)
+    if s:has_strchars
+      return strchars(a:str)
+    else
+      return strlen(substitute(a:str, '.', 'a', 'g'))
+    endif
+  endfunction
+
+  function! airline#util#strcharpart(...)
+    if s:has_strcharpart
+      return call('strcharpart',  a:000)
+    else
+      " does not handle multibyte chars :(
+      return a:1[(a:2):(a:3)]
+    endif
+  endfunction
+
+  function! airline#util#ignore_buf(name)
+    let pat = '\c\v'. get(g:, 'airline#ignore_bufadd_pat', '').
+          \ get(g:, 'airline#extensions#tabline#ignore_bufadd_pat',
+          \ '!|defx|gundo|nerd_tree|startify|tagbar|term://|undotree|vimfiler')
+    return match(a:name, pat) > -1
+  endfunction
+
+  function! airline#util#has_fugitive()
+    if !exists("s:has_fugitive")
+      let s:has_fugitive = exists('*FugitiveHead')
+    endif
+    return s:has_fugitive
+  endfunction
+
+  function! airline#util#has_zhihu()
+    if !has('nvim')
+      return 0
+    endif
+    try
+      call v:lua.require'zhihu'.setup()
+    catch
+      return 0
+    endtry
+    return 1
+  endfunction
+
+  function! airline#util#has_gina()
+    if !exists("s:has_gina")
+      let s:has_gina = (exists(':Gina') && v:version >= 800)
+    endif
+    return s:has_gina
+  endfunction
+
+
+  function! airline#util#has_lawrencium()
+    if !exists("s:has_lawrencium")
+      let s:has_lawrencium  = exists('*lawrencium#statusline')
+    endif
+    return s:has_lawrencium
+  endfunction
+
+  function! airline#util#has_vcscommand()
+    if !exists("s:has_vcscommand")
+      let s:has_vcscommand = exists('*VCSCommandGetStatusLine')
+    endif
+    return get(g:, 'airline#extensions#branch#use_vcscommand', 0) && s:has_vcscommand
+  endfunction
+
+  function! airline#util#has_custom_scm()
+    return !empty(get(g:, 'airline#extensions#branch#custom_head', ''))
+  endfunction
+
+  function! airline#util#doautocmd(event)
+    if !exists('#airline') && a:event !=? 'AirlineToggledOff'
+      " airline disabled
+      return
+    endif
+    try
+      exe printf("silent doautocmd %s User %s", s:nomodeline, a:event)
+    catch /^Vim\%((\a\+)\)\=:E48:/
+      " Catch: Sandbox mode
+      " no-op
+    endtry
+  endfunction
+
+  function! airline#util#themes(match)
+    let files = split(globpath(&rtp, 'autoload/airline/themes/'.a:match.'*.vim', 1), "\n")
+    return sort(map(files, 'fnamemodify(v:val, ":t:r")') + ('random' =~ a:match ? ['random'] : []))
+  endfunction
+
+  function! airline#util#stl_disabled(winnr)
+    " setting the statusline is disabled,
+    " either globally, per window, or per buffer
+    " w:airline_disabled is deprecated!
+    return get(g:, 'airline_disable_statusline', 0) ||
+    \ airline#util#getwinvar(a:winnr, 'airline_disable_statusline', 0) ||
+    \ airline#util#getwinvar(a:winnr, 'airline_disabled', 0) ||
+    \ airline#util#getbufvar(winbufnr(a:winnr), 'airline_disable_statusline', 0)
+  endfunction
+
+  function! airline#util#ignore_next_focusgain()
+    if has('win32')
+      " Setup an ignore for platforms that trigger FocusLost on calls to
+      " system(). macvim (gui and terminal) and Linux terminal vim do not.
+      let s:focusgained_ignore_time = localtime()
+    endif
+  endfunction
+
+  function! airline#util#is_popup_window(winnr)
+    " Keep the statusline active if it's a popup window
+    if exists('*win_gettype')
+      return win_gettype(a:winnr) ==# 'popup' || win_gettype(a:winnr) ==# 'autocmd'
+    else
+        return airline#util#getwinvar(a:winnr, '&buftype', '') ==# 'popup'
+    endif
+  endfunction
+
+  function! airline#util#try_focusgained()
+    " Ignore lasts for at most one second and is cleared on the first
+    " focusgained. We use ignore to prevent system() calls from triggering
+    " FocusGained (which occurs 100% on win32 and seem to sometimes occur under
+    " tmux).
+    let dt = localtime() - s:focusgained_ignore_time
+    let s:focusgained_ignore_time = 0
+    return dt >= 1
+  endfunction
+
+  function! airline#util#has_multiline()
+    " Returns true, if Vim supports multiline statusline (Vim 9.2.0083)
+    return (exists("+statuslineopt") &&
+      \ get(g:, "airline_multiline", 0))
+  endfunction
+
+else
+
+  def airline#util#winwidth(...args: list<any>): number
+    const nr = get(args, 0, 0)
+    # When statusline is on top, or using global statusline for Neovim
+    # always return the number of columns
+    if get(g:, 'airline_statusline_ontop', 0) || &laststatus > 2
+      return &columns
+    else
+      return winwidth(nr)
+    endif
+  enddef
+
+  def airline#util#shorten(text: string, winwidth: number, minwidth: number, ...args: list<any>): string
+    if airline#util#winwidth() < winwidth && len(split(text, '\zs')) > minwidth
+      if get(args, 0, 0)
+        # shorten from tail
+        return '…' .. matchstr(text, '.\{' .. minwidth .. '}$')
+      else
+        # shorten from beginning of string
+        return matchstr(text, '^.\{' .. minwidth .. '}') .. '…'
+      endif
+    else
+      return text
+    endif
+  enddef
+
+  def airline#util#wrap(text: string, minwidth: number): string
+    if minwidth > 0 && airline#util#winwidth() < minwidth
+      return ''
+    endif
+    return text
+  enddef
+
+  def airline#util#append(text: string, minwidth: number): string
+    if minwidth > 0 && airline#util#winwidth() < minwidth
+      return ''
+    endif
+    const prefix = s:spc == "\ua0" ? s:spc : s:spc .. s:spc
+    return empty(text) ? '' : prefix .. g:airline_left_alt_sep .. s:spc .. text
+  enddef
+
+  def airline#util#warning(msg: string)
+    echohl WarningMsg
+    echomsg "airline: " .. msg
+    echohl Normal
+  enddef
+
+  def airline#util#prepend(text: string, minwidth: number): string
+    if minwidth > 0 && airline#util#winwidth() < minwidth
+      return ''
+    endif
+    return empty(text) ? '' : text .. s:spc .. g:airline_right_alt_sep .. s:spc
+  enddef
+
+  def airline#util#getbufvar(bufnr: number, key: string, def: any): any
+    return getbufvar(bufnr, key, def)
+  enddef
+
+  def airline#util#getwinvar(winnr: number, key: string, def: any): any
+    return getwinvar(winnr, key, def)
+  enddef
+
+  def airline#util#exec_funcrefs(list: list<any>, ...args: list<any>): number
+    for Fn in list
+      var code = call(Fn, args)
+      if code != 0
+        return code
+      endif
+    endfor
+    return 0
+  enddef
+
+  def airline#util#strchars(str: string): number
+    if s:has_strchars
+      return strchars(str)
+    else
+      return strlen(substitute(str, '.', 'a', 'g'))
+    endif
+  enddef
+
+  def airline#util#strcharpart(...values: list<any>): string 
+    if s:has_strcharpart
+      return call('strcharpart',  values)
+    else
+      # does not handle multibyte chars :(
+      return values[1][values[2] : values[3]]
+    endif
+  enddef
+
+  def airline#util#ignore_buf(name: string): bool
+    var pat = '\c\v' .. get(g:, 'airline#ignore_bufadd_pat', '') .. get(g:, 'airline#extensions#tabline#ignore_bufadd_pat', '!|defx|gundo|nerd_tree|startify|tagbar|term://|undotree|vimfiler')
+    return match(name, pat) > -1
+  enddef
+
+  def airline#util#has_fugitive(): bool
+    if !exists("s:has_fugitive")
+      s:has_fugitive = exists('*FugitiveHead')
+    endif
+    return s:has_fugitive
+  enddef
+
+  def airline#util#has_zhihu(): number
+    return 0
+  enddef
+
+  def airline#util#has_gina(): bool
+    if !exists("s:has_gina")
+      s:has_gina = (exists(':Gina') && v:version >= 800)
+    endif
+    return s:has_gina
+  enddef
+
+  def airline#util#has_lawrencium(): bool 
+    if !exists("s:has_lawrencium")
+      s:has_lawrencium  = exists('*lawrencium#statusline')
+    endif
+    return s:has_lawrencium
+  enddef
+
+  def airline#util#has_vcscommand(): bool 
+    if !exists("s:has_vcscommand")
+      s:has_vcscommand = exists('*VCSCommandGetStatusLine')
+    endif
+    return get(g:, 'airline#extensions#branch#use_vcscommand', 0) && s:has_vcscommand
+  enddef
+
+  def airline#util#has_custom_scm(): bool
+    return !empty(get(g:, 'airline#extensions#branch#custom_head', ''))
+  enddef
+
+  def airline#util#doautocmd(event: string)
+    if !exists('#airline') && event !=? 'AirlineToggledOff'
+      # airline disabled
+      return
+    endif
+    try
+      exe printf("silent doautocmd %s User %s", s:nomodeline, event)
+    catch /^Vim\%((\a\+)\)\=:E48:/
+      # Catch: Sandbox mode
+      # no-op
+    endtry
+  enddef
+
+  def airline#util#themes(match_str: string): list<string>
+    const files = split(globpath(&rtp, 'autoload/airline/themes/' .. match_str .. '*.vim', true), "\n")
+    var theme_names = files->mapnew((_, val) => fnamemodify(val, ":t:r"))
+    if "random" =~ match_str
+      theme_names->add("random")
+    endif
+    return theme_names->sort()
+  enddef
+
+  def airline#util#stl_disabled(winnr: number): bool
+    # setting the statusline is disabled,
+    # either globally, per window, or per buffer
+    # w:airline_disabled is deprecated!
+    return get(g:, 'airline_disable_statusline', 0) ||
+          \ airline#util#getwinvar(winnr, 'airline_disable_statusline', 0) ||
+          \ airline#util#getwinvar(winnr, 'airline_disabled', 0) ||
+          \ airline#util#getbufvar(winbufnr(winnr), 'airline_disable_statusline', 0)
+  enddef
+
+  def airline#util#ignore_next_focusgain()
+    if has('win32')
+      # Setup an ignore for platforms that trigger FocusLost on calls to
+      # system(). macvim (gui and terminal) and Linux terminal vim do not.
+      s:focusgained_ignore_time = localtime()
+    endif
+  enddef
+
+  def airline#util#is_popup_window(winnr: number): bool
+    # Keep the statusline active if it's a popup window
+    if exists('*win_gettype')
+      return win_gettype(winnr) ==# 'popup' || win_gettype(winnr) ==# 'autocmd'
+    else
+      return airline#util#getwinvar(winnr, '&buftype', '') ==# 'popup'
+    endif
+  enddef
+
+  def airline#util#try_focusgained(): bool
+    # Ignore lasts for at most one second and is cleared on the first
+    # focusgained. We use ignore to prevent system() calls from triggering
+    # FocusGained (which occurs 100% on win32 and seem to sometimes occur under
+    # tmux).
+    const dt = localtime() - s:focusgained_ignore_time
+    s:focusgained_ignore_time = 0
+    return dt >= 1
+  enddef
+
+  def airline#util#has_multiline(): bool
+    # Returns true, if Vim supports multiline statusline (Vim 9.2.0083)
+    return (exists("+statuslineopt") &&
+          \ get(g:, "airline_multiline", 0))
+  enddef
+endif