diff --git a/nvim/autoload/user/plugin/coc.vim b/nvim/autoload/user/plugin/coc.vim
index f341261e..41da8dab 100644
--- a/nvim/autoload/user/plugin/coc.vim
+++ b/nvim/autoload/user/plugin/coc.vim
@@ -51,13 +51,23 @@ function! user#plugin#coc#init() abort
     autocmd User CocJumpPlaceholder silent call CocActionAsync('showSignatureHelp')
 
     " Auto format
-    autocmd FocusLost,BufLeave *.go silent call CocActionAsync('format')
+    autocmd FocusLost,BufLeave *.go call user#plugin#coc#auto_format()
 
     " Override plugin commands
     autocmd VimEnter * command! -nargs=0 CocRestart :silent call coc#rpc#restart()
   augroup END
 endfunction
 
+function! user#plugin#coc#auto_format() abort
+  if &readonly || !&modifiable
+    return
+  endif
+  if mode() ==# 'n'
+    return
+  endif
+  silent call CocActionAsync('format')
+endfunction
+
 "  Custom actions
 "-----------------------------------------------
 nnoremap <Plug>(coc-hover) <Cmd>call CocActionAsync('doHover')<CR>