diff -r 3e74d3cc500f -r c97b936d8bb5 mercurial/hgweb/hgweb_mod.py
--- a/mercurial/hgweb/hgweb_mod.py	Mon Mar 19 21:09:23 2018 +0900
+++ b/mercurial/hgweb/hgweb_mod.py	Fri Mar 16 21:39:32 2018 +0900
@@ -198,7 +198,8 @@
 
     def sendtemplate(self, name, **kwargs):
         """Helper function to send a response generated from a template."""
-        self.res.setbodygen(self.tmpl(name, **kwargs))
+        kwargs = pycompat.byteskwargs(kwargs)
+        self.res.setbodygen(self.tmpl.generate(name, kwargs))
         return self.res.sendresponse()
 
 class hgweb(object):