diff --git a/README.md b/README.md
index e57708f..d01fb48 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # SVG-edit for YunoHost
 
 [![Integration level](https://dash.yunohost.org/integration/svgedit.svg)](https://dash.yunohost.org/appci/app/svgedit) ![](https://ci-apps.yunohost.org/ci/badges/svgedit.status.svg) ![](https://ci-apps.yunohost.org/ci/badges/svgedit.maintain.svg)  
-[![Install SVG-edit with YunoHost](https://install-app.yunohost.org/install-with-yunohost.png)](https://install-app.yunohost.org/?app=svgedit)
+[![Install SVG-edit with YunoHost](https://install-app.yunohost.org/install-with-yunohost.svg)](https://install-app.yunohost.org/?app=svgedit)
 
 *[Lire ce readme en français.](./README_fr.md)*
 
diff --git a/README_fr.md b/README_fr.md
index 0e89774..a911388 100644
--- a/README_fr.md
+++ b/README_fr.md
@@ -1,7 +1,7 @@
 # SVG-edit pour YunoHost
 
 [![Niveau d'intégration](https://dash.yunohost.org/integration/svgedit.svg)](https://dash.yunohost.org/appci/app/svgedit) ![](https://ci-apps.yunohost.org/ci/badges/svgedit.status.svg) ![](https://ci-apps.yunohost.org/ci/badges/svgedit.maintain.svg)  
-[![Installer SVG-edit avec YunoHost](https://install-app.yunohost.org/install-with-yunohost.png)](https://install-app.yunohost.org/?app=svgedit)
+[![Installer SVG-edit avec YunoHost](https://install-app.yunohost.org/install-with-yunohost.svg)](https://install-app.yunohost.org/?app=svgedit)
 
 *[Read this readme in english.](./README.md)* 
 
diff --git a/check_process b/check_process
index 780d220..844aae7 100644
--- a/check_process
+++ b/check_process
@@ -14,12 +14,8 @@
 		upgrade=1
 		backup_restore=1
 		multi_instance=1
-		# incorrect_path=1
 		port_already_use=0
 		change_url=1
-;;; Levels
-	# If the level 5 (Package linter) is forced to 1. Please add justifications here.
-	Level 5=auto
 ;;; Options
 Email=
 Notification=none
diff --git a/manifest.json b/manifest.json
index b2eb540..a1a3492 100644
--- a/manifest.json
+++ b/manifest.json
@@ -18,7 +18,7 @@
         "name": "Luc Didry"
     },
     "requirements": {
-        "yunohost": ">> 3.8.1"
+        "yunohost": ">> 4.1.0"
     },
     "multi_instance": true,
     "services": [
diff --git a/scripts/install b/scripts/install
index aed17bc..3b37710 100755
--- a/scripts/install
+++ b/scripts/install
@@ -47,7 +47,6 @@ ynh_script_progression --message="Storing installation settings..." --weight=1
 
 ynh_app_setting_set --app=$app --key=domain --value=$domain
 ynh_app_setting_set --app=$app --key=path --value=$path_url
-ynh_app_setting_set --app=$app --key=is_public --value=$is_public
 
 # INSTALL DEPENDENCIES
 #=================================================
@@ -96,12 +95,12 @@ chown -R $app: $final_path
 #=================================================
 # SETUP SSOWAT
 #=================================================
-ynh_script_progression --message="Configuring SSOwat..." --weight=1
+ynh_script_progression --message="Configuring permissions..." --weight=1
 
 # Make app public if necessary or protect it
 if [ $is_public -eq 1 ]
 then
-	ynh_permission_update --permission "main" --add "visitors"
+	ynh_permission_update --permission="main" --add="visitors"
 fi
 
 #=================================================
diff --git a/scripts/remove b/scripts/remove
index 102f725..de89e88 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -43,6 +43,14 @@ ynh_script_progression --message="Removing NGINX web server configuration..." --
 # Remove the dedicated NGINX config
 ynh_remove_nginx_config
 
+#=================================================
+# REMOVE DEDICATED USER
+#=================================================
+ynh_script_progression --message="Removing the dedicated system user..." --weight=1
+
+# Delete a system user
+ynh_system_user_delete --username=$app
+
 #=================================================
 # END OF SCRIPT
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 2cd1f07..26316a6 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -18,7 +18,6 @@ app=$YNH_APP_INSTANCE_NAME
 
 domain=$(ynh_app_setting_get --app=$app --key=domain)
 path_url=$(ynh_app_setting_get --app=$app --key=path)
-is_public=$(ynh_app_setting_get --app=$app --key=is_public)
 final_path=$(ynh_app_setting_get --app=$app --key=final_path)
 
 #=================================================
@@ -47,6 +46,13 @@ if [ -z "$final_path" ]; then
 	ynh_app_setting_set --app=$app --key=final_path --value=$final_path
 fi
 
+# Cleaning legacy permissions
+if ynh_legacy_permissions_exists; then
+	ynh_legacy_permissions_delete_all
+
+	ynh_app_setting_delete --app=$app --key=is_public
+fi
+
 #=================================================
 # BACKUP BEFORE UPGRADE THEN ACTIVE TRAP
 #=================================================
@@ -61,6 +67,19 @@ ynh_clean_setup () {
 # Exit if an error occurs during the execution of the script
 ynh_abort_if_errors
 
+#=================================================
+# DOWNLOAD, CHECK AND UNPACK SOURCE
+#=================================================
+
+if [ "$upgrade_type" == "UPGRADE_APP" ]
+then
+	ynh_script_progression --message="Upgrading source files..." --time --weight=1
+
+	#ynh_secure_remove "$final_path"
+	# Download, check integrity, uncompress and patch the source from app.src
+	ynh_setup_source --dest_dir="$final_path"
+fi
+
 #=================================================
 # UPGRADE DEPENDENCIES
 #=================================================
@@ -68,16 +87,6 @@ ynh_script_progression --message="Upgrading dependencies..." --weight=6
 
 ynh_install_app_dependencies $pkg_dependencies
 
-#=================================================
-# DOWNLOAD, CHECK AND UNPACK SOURCE
-#=================================================
-ynh_script_progression --message="Setting up source files..." --weight=5
-
-ynh_app_setting_set --app=$app --key=final_path --value=$final_path
-# Download, check integrity, uncompress and patch the source from app.src
-ynh_secure_remove "$final_path"
-ynh_setup_source --dest_dir="$final_path"
-
 #=================================================
 # CREATE DEDICATED USER
 #=================================================