diff -r 47719d7c581f -r 4265bfb53dd3 mercurial/hgweb/webcommands.py
--- a/mercurial/hgweb/webcommands.py	Tue Dec 04 17:04:19 2018 -0500
+++ b/mercurial/hgweb/webcommands.py	Sun Dec 09 23:48:50 2018 -0500
@@ -858,7 +858,7 @@
     if 'context' in web.req.qsparams:
         context = parsecontext(web.req.qsparams['context'])
     else:
-        context = parsecontext(web.config('web', 'comparisoncontext', '5'))
+        context = parsecontext(web.config('web', 'comparisoncontext'))
 
     def filelines(f):
         if f.isbinary():