diff --git a/scripts/upgrade b/scripts/upgrade
index ade6bfd..f1079e3 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -3,16 +3,7 @@
 # Exit on command errors and treat unset variables as an error
 set -eu
 
-# This is a multi-instance app, meaning it can be installed several times independently
-# The id of the app as stated in the manifest is available as $YNH_APP_ID
-# The instance number is available as $YNH_APP_INSTANCE_NUMBER (equals "1", "2", ...)
-# The app instance name is available as $YNH_APP_INSTANCE_NAME
-#    - the first time the app is installed, YNH_APP_INSTANCE_NAME = ynhexample
-#    - the second time the app is installed, YNH_APP_INSTANCE_NAME = ynhexample__2
-#    - ynhexample__{N} for the subsequent installations, with N=3,4, ...
-# The app instance name is probably what you are interested the most, since this is
-# guaranteed to be unique. This is a good unique identifier to define installation path,
-# db names, ...
+# See comments in install script
 app=$YNH_APP_INSTANCE_NAME
 
 # Source YunoHost helpers
@@ -24,6 +15,8 @@ path_url=$(ynh_app_setting_get "$app" path_url)
 portNginx=$(ynh_find_port 8080)
 portUnicorn=$(ynh_find_port 9080)
 
+path_url=${path_url%/} 
+
 # if path do not begin with / add a / at the begining
 if [ "${path_url:0:1}" != "/" ]; then
        path_url="/$path_url"