diff -r 8fba319750c2 -r 6ff6e1d6b5b8 mercurial/hgweb/hgwebdir_mod.py
--- a/mercurial/hgweb/hgwebdir_mod.py	Wed Feb 28 15:20:41 2018 -0500
+++ b/mercurial/hgweb/hgwebdir_mod.py	Thu Mar 08 23:10:46 2018 +0900
@@ -34,6 +34,7 @@
     pycompat,
     scmutil,
     templater,
+    templateutil,
     ui as uimod,
     util,
 )
@@ -370,7 +371,7 @@
             virtual = req.dispatchpath.strip('/')
             tmpl = self.templater(req, nonce)
             ctype = tmpl('mimetype', encoding=encoding.encoding)
-            ctype = templater.stringify(ctype)
+            ctype = templateutil.stringify(ctype)
 
             # Global defaults. These can be overridden by any handler.
             res.status = '200 Script output follows'