diff --git a/scripts/install b/scripts/install
index 549351d..51ef5a4 100755
--- a/scripts/install
+++ b/scripts/install
@@ -10,8 +10,28 @@ ynh_script_progression "Setting up source files..."
 
 ynh_setup_source --dest_dir="$install_dir/app"
 
-chmod -R 750 "$install_dir"
-chown -R $app:www-data "$install_dir"
+chmod -R "u=rX,g=rX,o=" "$install_dir"
+chown -R "$app:www-data" "$install_dir"
+
+#=================================================
+# ADD A CONFIGURATION
+#=================================================
+ynh_script_progression "Adding $app's configuration..."
+
+mkdir -p "$install_dir/app/data/_data_/_default_/configs"
+ynh_config_add --template="application.ini" --destination="$install_dir/app/data/_data_/_default_/configs/application.ini"
+
+chmod -R "u=rwX,g=,o=" "$install_dir/app/data"
+chown -R "$app:$app" "$install_dir/app/data"
+
+#=================================================
+# SETUP SSO
+#=================================================
+ynh_script_progression "Applying SSO patch..."
+
+ynh_config_add --template="sso.php" --destination="$install_dir/index.php"
+chmod "u=rX,g=,o=" "$install_dir/index.php"
+chown "$app:www-data" "$install_dir/index.php"
 
 #=================================================
 # SYSTEM CONFIGURATION
@@ -24,28 +44,6 @@ ynh_config_add_nginx
 
 ynh_config_add_logrotate
 
-#=================================================
-# APP INITIAL CONFIGURATION
-#=================================================
-# ADD A CONFIGURATION
-#=================================================
-ynh_script_progression "Adding $app's configuration..."
-
-mkdir -p "$install_dir/app/data/_data_/_default_/configs"
-ynh_config_add --template="application.ini" --destination="$install_dir/app/data/_data_/_default_/configs/application.ini"
-
-chown -R $app:$app "$install_dir/app/data"
-chmod -R 600 "$install_dir/app/data"
-
-#=================================================
-# SETUP SSO
-#=================================================
-ynh_script_progression "Applying SSO patch..."
-
-ynh_config_add --template="sso.php" --destination="$install_dir/index.php"
-chown $app:www-data "$install_dir/index.php"
-chmod 750 "$install_dir/index.php"
-
 #=================================================
 # END OF SCRIPT
 #=================================================
diff --git a/scripts/restore b/scripts/restore
index a74297c..de26cae 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -11,10 +11,13 @@ ynh_script_progression "Restoring the app main directory..."
 
 ynh_restore "$install_dir"
 
-chmod -R 750 "$install_dir"
-chown -R $app:www-data "$install_dir"
-chmod 600 "$install_dir/app/data/_data_/_default_/configs/application.ini"
-chown -R $app:$app "$install_dir/app/data/_data_"
+chmod -R "u=rX,g=rX,o=" "$install_dir"
+chown -R "$app:www-data" "$install_dir"
+
+chmod -R "u=rwX,g=,o=" "$install_dir/app/data"
+chown -R "$app:$app" "$install_dir/app/data"
+
+chmod "u=rX,g=,o=" "$install_dir/index.php"
 
 #=================================================
 # RESTORE SYSTEM CONFIGURATIONS
@@ -32,7 +35,7 @@ ynh_restore "/etc/logrotate.d/$app"
 #=================================================
 ynh_script_progression "Reloading NGINX web server and $app's service..."
 
-ynh_systemctl --service=php$php_version-fpm --action=reload
+ynh_systemctl --service="php$php_version-fpm" --action=reload
 ynh_systemctl --service=nginx --action=reload
 
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 11da544..cd1624b 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -9,13 +9,12 @@ source /usr/share/yunohost/helpers
 ynh_script_progression "Ensuring downward compatibility..."
 
 # Do something when upgrading from 2.3.2~ynh1 or lower
-if ynh_app_upgrading_from_version_before_or_equal_to 2.28.4~ynh1
-then
+if ynh_app_upgrading_from_version_before_or_equal_to 2.28.4~ynh1; then
     # Move everything inside a $install_dir/app/ subfolder
     # This allows to have a $install_dir/index.php handling the SSO
-    mkdir -p $install_dir/app
+    mkdir -p "$install_dir/app"
     # Ugly way to not return an error when moving everything to a subfolter of the same folder https://stackoverflow.com/a/43262922
-    find $install_dir -maxdepth 1 -mindepth 1 -not -name app -exec mv -t $install_dir/app {} +
+    find "$install_dir" -maxdepth 1 -mindepth 1 -not -name app -exec mv -t "$install_dir/app" {} +
 fi
 
 #=================================================
@@ -25,8 +24,27 @@ ynh_script_progression "Upgrading source files..."
 
 ynh_setup_source --dest_dir="$install_dir/app" --full_replace=1 --keep="data/_data_/_default_/configs/application.ini"
 
-chmod -R 750 "$install_dir"
-chown -R $app:www-data "$install_dir"
+chmod -R "u=rX,g=rX,o=" "$install_dir"
+chown -R "$app:www-data" "$install_dir"
+
+#=================================================
+# UPDATE A CONFIG FILE
+#=================================================
+#ynh_script_progression "Updating configuration..."
+
+#ynh_config_add --template="application.ini" --destination="$install_dir/app/data/_data_/_default_/configs/application.ini"
+
+chmod -R "u=rwX,g=,o=" "$install_dir/app/data"
+chown -R "$app:$app" "$install_dir/app/data"
+
+#=================================================
+# SETUP SSO
+#=================================================
+ynh_script_progression "Applying SSO patch..."
+
+ynh_config_add --template="sso.php" --destination="$install_dir/index.php"
+chmod "u=rX,g=,o=" "$install_dir/index.php"
+chown "$app:www-data" "$install_dir/index.php"
 
 #=================================================
 # REAPPLY SYSTEM CONFIGURATIONS
@@ -39,27 +57,6 @@ ynh_config_add_nginx
 
 ynh_config_add_logrotate
 
-#=================================================
-# RECONFIGURE THE APP (UPDATE CONF, APPLY MIGRATIONS...)
-#=================================================
-# UPDATE A CONFIG FILE
-#=================================================
-#ynh_script_progression "Updating configuration..."
-
-#ynh_config_add --template="application.ini" --destination="$install_dir/app/data/_data_/_default_/configs/application.ini"
-
-chmod -R 600 "$install_dir/app/data"
-chown -R $app:$app "$install_dir/app/data"
-
-#=================================================
-# SETUP SSO
-#=================================================
-ynh_script_progression "Applying SSO patch..."
-
-ynh_config_add --template="sso.php" --destination="$install_dir/index.php"
-chown $app:www-data "$install_dir/index.php"
-chmod 750 "$install_dir/index.php"
-
 #=================================================
 # END OF SCRIPT
 #=================================================