Default custom header: use * for corners

autoload/startify/fortune.vim

@@ -118,7 +118,7 @@ endfunction
 " Function: s:draw_box {{{1
 function! s:draw_box(lines) abort
   let longest_line = max(map(copy(a:lines), 'len(v:val)'))
-  let topbottom = '|'. repeat('-', longest_line + 2) .'|'
+  let topbottom = '*'. repeat('-', longest_line + 2) .'*'
   let lines = [topbottom]
   for l in a:lines
     let offset = longest_line - len(l)