diff --git a/autoload/airline/extensions/zoomwintab.vim b/autoload/airline/extensions/zoomwintab.vim
index d7adc940..7e1b0c72 100644
--- a/autoload/airline/extensions/zoomwintab.vim
+++ b/autoload/airline/extensions/zoomwintab.vim
@@ -12,14 +12,16 @@ endif
 
 let g:loaded_vim_airline_zoomwintab = 1
 
-let s:zoomwintab_status_zoomed_in = get(g:, 'airline#extensions#zoomwintab#status_zoomed_in', g:airline_left_alt_sep.' Zoomed')
-let s:zoomwintab_status_zoomed_out = get(g:, 'airline#extensions#zoomwintab#status_zoomed_out', '')
+let s:zoomwintab_status_zoomed_in =
+  \ get(g:, 'airline#extensions#zoomwintab#status_zoomed_in', g:airline_left_alt_sep.' Zoomed')
+let s:zoomwintab_status_zoomed_out =
+  \ get(g:, 'airline#extensions#zoomwintab#status_zoomed_out', '')
 
-function! airline#extensions#zoomwintab#apply(...)
+function! airline#extensions#zoomwintab#apply(...) abort
   call airline#extensions#prepend_to_section('gutter',
     \ exists('t:zoomwintab') ? s:zoomwintab_status_zoomed_in : s:zoomwintab_status_zoomed_out)
 endfunction
 
-function! airline#extensions#zoomwintab#init(ext)
+function! airline#extensions#zoomwintab#init(ext) abort
   call a:ext.add_statusline_func('airline#extensions#zoomwintab#apply')
 endfunction