--- a/mercurial/hgweb/hgwebdir_mod.py	Fri Jul 20 09:08:20 2018 +0200
+++ b/mercurial/hgweb/hgwebdir_mod.py	Wed Jul 25 10:05:24 2018 +0200
@@ -514,7 +514,7 @@
         logourl = config('web', 'logourl')
         logoimg = config('web', 'logoimg')
         staticurl = (config('web', 'staticurl')
-                     or req.apppath + '/static/')
+                     or req.apppath.rstrip('/') + '/static/')
         if not staticurl.endswith('/'):
             staticurl += '/'