mercurial/hgweb/hgwebdir_mod.py

--- a/mercurial/hgweb/hgwebdir_mod.py	Tue Jun 09 12:57:57 2015 -0400
+++ b/mercurial/hgweb/hgwebdir_mod.py	Sun Jun 07 17:14:17 2015 -0700
@@ -98,6 +98,9 @@
             u = ui.ui()
             u.setconfig('ui', 'report_untrusted', 'off', 'hgwebdir')
             u.setconfig('ui', 'nontty', 'true', 'hgwebdir')
+            # displaying bundling progress bar while serving feels wrong and may
+            # break some wsgi implementations.
+            u.setconfig('progress', 'disable', 'true', 'hgweb')
 
         if not isinstance(self.conf, (dict, list, tuple)):
             map = {'paths': 'hgweb-paths'}