[Minor] Fix misprint

diff --git a/lualib/lua_mime.lua b/lualib/lua_mime.lua
index 75e5d11f80b676a91792b537c09a589ceb51af8f..bb65dc9ba7573e9d9bc64e8febdc078634cfe397 100644 (file)
--- a/lualib/lua_mime.lua
+++ b/lualib/lua_mime.lua
@@ -941,7 +941,7 @@ exports.get_displayed_text_part = function(task)
   end
 
   if text_part then
-    local word_count = html_part:get_words_count() or 0
+    local word_count = text_part:get_words_count() or 0
     if word_count >= 10 then
       -- Arbitrary minimum threshold, e.g. I believe it's minimum sane
       return text_part