diff --git a/autoload/airline/highlighter.vim b/autoload/airline/highlighter.vim
index d3b7de90..249f2ee6 100644
--- a/autoload/airline/highlighter.vim
+++ b/autoload/airline/highlighter.vim
@@ -515,7 +515,7 @@ else
       airline#highlighter#highlight(['normal'])
     endif
   enddef
-  def! airline#highlighter#add_separator(from: string, to: string, inverse: bool): void # {{{2
+  def airline#highlighter#add_separator(from: string, to: string, inverse: bool): void # {{{2
     s:separators[from .. to] = [from, to, inverse]
     s:exec_separator({}, from, to, inverse, '')
   enddef