diff --git a/doc/.gitkeep b/doc/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/doc/DESCRIPTION.md b/doc/DESCRIPTION.md
new file mode 100644
index 0000000..5cdf2cb
--- /dev/null
+++ b/doc/DESCRIPTION.md
@@ -0,0 +1 @@
+Photoview is a simple and user-friendly photo gallery that's made for photographers and aims to provide an easy and fast way to navigate directories, with thousands of high resolution photos.
diff --git a/doc/DISCLAIMER.md b/doc/DISCLAIMER.md
new file mode 100644
index 0000000..e69de29
diff --git a/doc/screenshots/.gitkeep b/doc/screenshots/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/doc/screenshots/screenshot1.png b/doc/screenshots/screenshot1.png
new file mode 100644
index 0000000..6fcd323
Binary files /dev/null and b/doc/screenshots/screenshot1.png differ
diff --git a/manifest.json b/manifest.json
index 568a077..5c76567 100644
--- a/manifest.json
+++ b/manifest.json
@@ -8,13 +8,20 @@
     },
     "version": "2.3.9~ynh2",
     "url": "https://photoview.github.io/",
+    "upstream": {
+        "license": "AGPL-3.0-only",
+        "website": "https://photoview.github.io/",
+        "demo": "https://photos.qpqp.dk/",
+        "admindoc": "https://photoview.github.io/docs/",
+        "code": "https://github.com/photoview/photoview"
+    },
     "license": "AGPL-3.0-only",
     "maintainer": {
         "name": "Jules Bertholet",
         "email": "jules.bertholet@gmail.com"
     },
     "requirements": {
-        "yunohost": ">= 4.1.7"
+        "yunohost": ">= 4.3.0"
     },
     "multi_instance": true,
     "services": [
@@ -22,11 +29,15 @@
         "mysql"
     ],
     "arguments": {
-        "install" : [
+        "install": [
             {
                 "name": "domain",
-                "type": "domain",
-                "example": "example.com"
+                "type": "domain"
+            },
+            {
+                "name": "is_public",
+                "type": "boolean",
+                "default": true
             },
             {
                 "name": "mapbox_token",
@@ -41,11 +52,6 @@
                     "en": "Required for mapping features. You can get one for free at https://www.mapbox.com/",
                     "fr": "Nécessaire pour les fonctionnalités cartographiques. Vous pouvez en obtenir une gratuitement à https://www.mapbox.com/"
                 }
-            },
-            {
-                "name": "is_public",
-                "type": "boolean",
-                "default": true
             }
         ]
     }
diff --git a/scripts/backup b/scripts/backup
index c4a4396..8a1d93f 100755
--- a/scripts/backup
+++ b/scripts/backup
@@ -14,7 +14,7 @@ source /usr/share/yunohost/helpers
 # MANAGE SCRIPT FAILURE
 #=================================================
 
-ynh_clean_setup() {
+ynh_clean_setup () {
 	true
 }
 # Exit if an error occurs during the execution of the script
@@ -28,9 +28,9 @@ ynh_print_info --message="Loading installation settings..."
 app=$YNH_APP_INSTANCE_NAME
 
 final_path=$(ynh_app_setting_get --app=$app --key=final_path)
-data_path=$(ynh_app_setting_get --app=$app --key=data_path)
 domain=$(ynh_app_setting_get --app=$app --key=domain)
 db_name=$(ynh_app_setting_get --app=$app --key=db_name)
+data_path=$(ynh_app_setting_get --app=$app --key=data_path)
 
 #=================================================
 # DECLARE DATA AND CONF FILES TO BACKUP
@@ -69,18 +69,12 @@ ynh_backup --src_path="/etc/logrotate.d/$app"
 
 ynh_backup --src_path="/etc/systemd/system/$app.service"
 
-#=================================================
-# BACKUP VARIOUS FILES
-#=================================================
-
-ynh_backup --src_path="/var/log/$app"
-
 #=================================================
 # BACKUP THE MYSQL DATABASE
 #=================================================
 ynh_print_info --message="Backing up the MySQL database..."
 
-ynh_mysql_dump_db --database="$db_name" >db.sql
+ynh_mysql_dump_db --database="$db_name" > db.sql
 
 #=================================================
 # END OF SCRIPT
diff --git a/scripts/change_url b/scripts/change_url
index 448926b..773a160 100644
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -40,13 +40,14 @@ data_path=$(ynh_app_setting_get --app=$app --key=data_path)
 mapbox_token=$(ynh_app_setting_get --app=$app --key=mapbox_token)
 
 #=================================================
-# BACKUP BEFORE UPGRADE THEN ACTIVE TRAP
+# BACKUP BEFORE CHANGE URL THEN ACTIVE TRAP
 #=================================================
 ynh_script_progression --message="Backing up the app before changing its URL (may take a while)..." --weight=35
 
 # Backup the current version of the app
 ynh_backup_before_upgrade
-ynh_clean_setup() {
+ynh_clean_setup () {
+	ynh_clean_check_starting
 	# Remove the new domain config file, the remove script won't do it as it doesn't know yet its location.
 	ynh_secure_remove --file="/etc/nginx/conf.d/$new_domain.d/$app.conf"
 
@@ -61,7 +62,8 @@ ynh_abort_if_errors
 #=================================================
 
 change_domain=0
-if [ "$old_domain" != "$new_domain" ]; then
+if [ "$old_domain" != "$new_domain" ]
+then
 	change_domain=1
 fi
 
@@ -84,7 +86,8 @@ ynh_script_progression --message="Updating NGINX web server configuration..." --
 nginx_conf_path=/etc/nginx/conf.d/$old_domain.d/$app.conf
 
 # Change the domain for NGINX
-if [ $change_domain -eq 1 ]; then
+if [ $change_domain -eq 1 ]
+then
 	# Delete file checksum for the old conf file location
 	ynh_delete_file_checksum --file="$nginx_conf_path"
 	mv $nginx_conf_path /etc/nginx/conf.d/$new_domain.d/$app.conf
@@ -107,6 +110,7 @@ ynh_add_config --template=".env" --destination="$final_path/output/.env"
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
+# Start a systemd service
 ynh_systemd_action --service_name=$app --action="start" --log_path="/var/log/$app/$app.log"
 
 #=================================================
diff --git a/scripts/install b/scripts/install
index 8fed52e..6295af3 100755
--- a/scripts/install
+++ b/scripts/install
@@ -13,8 +13,8 @@ source /usr/share/yunohost/helpers
 # MANAGE SCRIPT FAILURE
 #=================================================
 
-ynh_clean_setup() {
-	true
+ynh_clean_setup () {
+	ynh_clean_check_starting
 }
 # Exit if an error occurs during the execution of the script
 ynh_abort_if_errors
@@ -39,7 +39,6 @@ final_path=/opt/yunohost/$app
 test ! -e "$final_path" || ynh_die --message="This path already contains a folder"
 
 data_path=/home/yunohost.app/$app
-test ! -e "$data_path" || ynh_die --message="This path already contains a folder"
 
 # Register (book) web path
 ynh_webpath_register --app=$app --domain=$domain --path_url=$path_url
@@ -56,7 +55,7 @@ ynh_app_setting_set --app=$app --key=mapbox_token --value=$mapbox_token
 #=================================================
 # STANDARD MODIFICATIONS
 #=================================================
-# FIND PORTS
+# FIND AND OPEN A PORT
 #=================================================
 ynh_script_progression --message="Finding an available port..." --weight=1
 
@@ -70,6 +69,8 @@ ynh_app_setting_set --app=$app --key=port --value=$port
 ynh_script_progression --message="Installing dependencies..." --weight=60
 
 install_dependencies
+set_go_vars
+set_node_vars
 
 #=================================================
 # CREATE DEDICATED USER
@@ -136,11 +137,12 @@ build_ui
 ynh_script_progression --message="Configuring a systemd service..." --weight=1
 
 # Create a dedicated systemd config
-ynh_add_systemd_config --service=$app
+ynh_add_systemd_config
 
 #=================================================
 # ADD A CONFIGURATION
 #=================================================
+ynh_script_progression --message="Adding a configuration file..."
 
 ynh_add_config --template=".env" --destination="$final_path/output/.env"
 
@@ -177,7 +179,8 @@ ynh_systemd_action --service_name=$app --action="start" --log_path="/var/log/$ap
 ynh_script_progression --message="Configuring permissions..." --weight=1
 
 # Make app public if necessary
-if [ $is_public -eq 1 ]; then
+if [ $is_public -eq 1 ]
+then
 	# Everyone can access the app.
 	# The "main" permission is automatically created before the install script.
 	ynh_permission_update --permission="main" --add="visitors"
diff --git a/scripts/remove b/scripts/remove
index ea82bfa..f3f4f59 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -43,7 +43,15 @@ ynh_script_progression --message="Stopping and removing the systemd service..."
 
 # Remove the dedicated systemd config
 ynh_remove_systemd_config
-I
+
+#=================================================
+# REMOVE LOGROTATE CONFIGURATION
+#=================================================
+ynh_script_progression --message="Removing logrotate configuration..." --weight=1
+
+# Remove the app-specific logrotate config
+ynh_remove_logrotate
+
 #=================================================
 # REMOVE THE MYSQL DATABASE
 #=================================================
@@ -52,14 +60,6 @@ ynh_script_progression --message="Removing the MySQL database..." --weight=1
 # Remove a database if it exists, along with the associated user
 ynh_mysql_remove_db --db_user=$db_user --db_name=$db_name
 
-#=================================================
-# REMOVE DEPENDENCIES
-#=================================================
-ynh_script_progression --message="Removing dependencies..." --weight=5
-
-# Remove metapackage and its dependencies
-ynh_remove_app_dependencies
-
 #=================================================
 # REMOVE APP MAIN DIR
 #=================================================
@@ -85,12 +85,14 @@ ynh_script_progression --message="Removing NGINX web server configuration..." --
 ynh_remove_nginx_config
 
 #=================================================
-# REMOVE LOGROTATE CONFIGURATION
+# REMOVE DEPENDENCIES
 #=================================================
-ynh_script_progression --message="Removing logrotate configuration..." --weight=1
+ynh_script_progression --message="Removing dependencies..." --weight=5
 
-# Remove the app-specific logrotate config
-ynh_remove_logrotate
+# Remove metapackage and its dependencies
+ynh_remove_go
+ynh_remove_nodejs
+ynh_remove_app_dependencies
 
 #=================================================
 # SPECIFIC REMOVE
@@ -101,20 +103,6 @@ ynh_remove_logrotate
 # Remove the log files
 ynh_secure_remove --file="/var/log/$app"
 
-#=================================================
-# REMOVE GO
-#=================================================
-ynh_script_progression --message="Removing Go..." --weight=1
-
-ynh_remove_go
-
-#=================================================
-# REMOVE NODE
-#=================================================
-ynh_script_progression --message="Removing Node.js..." --weight=1
-
-ynh_remove_nodejs
-
 #=================================================
 # GENERIC FINALIZATION
 #=================================================
diff --git a/scripts/restore b/scripts/restore
index 96c7095..5c0042c 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -15,7 +15,7 @@ source /usr/share/yunohost/helpers
 #=================================================
 
 ynh_clean_setup() {
-	true
+	ynh_clean_check_starting
 }
 # Exit if an error occurs during the execution of the script
 ynh_abort_if_errors
@@ -42,36 +42,26 @@ mapbox_token=$(ynh_app_setting_get --app=$app --key=mapbox_token)
 #=================================================
 ynh_script_progression --message="Validating restoration parameters..." --weight=1
 
-ynh_webpath_available --domain=$domain --path_url=$path_url ||
-	ynh_die --message="Path not available: ${domain}${path_url}"
-test ! -d $final_path ||
-	ynh_die --message="There is already a directory: $final_path "
+test ! -d $final_path \
+	|| ynh_die --message="There is already a directory: $final_path "
 
 #=================================================
 # STANDARD RESTORATION STEPS
 #=================================================
 # RESTORE THE NGINX CONFIGURATION
 #=================================================
+ynh_script_progression --message="Restoring the NGINX web server configuration..."
 
 ynh_restore_file --origin_path="/etc/nginx/conf.d/$domain.d/$app.conf"
 
 #=================================================
 # RECREATE THE DEDICATED USER
 #=================================================
-
 ynh_script_progression --message="Recreating the dedicated system user..." --weight=1
 
 # Create the dedicated user (if not existing)
 ynh_system_user_create --username=$app --home_dir="$final_path"
 
-#=================================================
-# REINSTALL DEPENDENCIES
-#=================================================
-ynh_script_progression --message="Reinstalling dependencies..." --weight=30
-
-# Define and install dependencies
-install_dependencies
-
 #=================================================
 # RESTORE THE APP MAIN DIR
 #=================================================
@@ -84,7 +74,6 @@ set_permissions
 #=================================================
 # RESTORE THE APP DATA DIR
 #=================================================
-
 ynh_script_progression --message="Restoring the app data directory..." --weight=1
 
 ynh_restore_file --origin_path="$data_path" --not_mandatory
@@ -93,6 +82,16 @@ set_permissions
 
 #=================================================
 # SPECIFIC RESTORATION
+#=================================================
+# REINSTALL DEPENDENCIES
+#=================================================
+ynh_script_progression --message="Reinstalling dependencies..." --weight=30
+
+# Define and install dependencies
+install_dependencies
+set_go_vars
+set_node_vars
+
 #=================================================
 # RESTORE THE MYSQL DATABASE
 #=================================================
@@ -100,21 +99,7 @@ ynh_script_progression --message="Restoring the MySQL database..." --weight=1
 
 db_pwd=$(ynh_app_setting_get --app=$app --key=mysqlpwd)
 ynh_mysql_setup_db --db_user=$db_user --db_name=$db_name --db_pwd=$db_pwd
-ynh_mysql_connect_as --user=$db_user --password=$db_pwd --database=$db_name <./db.sql
-
-#=================================================
-# RESTORE GO
-#=================================================
-ynh_script_progression --message="Restoring Go..." --weight=1
-
-set_go_vars
-
-#=================================================
-# RESTORE NODE.JS
-#=================================================
-ynh_script_progression --message="Restoring Node.js..." --weight=1
-
-set_node_vars
+ynh_mysql_connect_as --user=$db_user --password=$db_pwd --database=$db_name < ./db.sql
 
 #=================================================
 # RESTORE SYSTEMD
@@ -124,6 +109,15 @@ ynh_script_progression --message="Restoring the systemd configuration..." --weig
 ynh_restore_file --origin_path="/etc/systemd/system/$app.service"
 systemctl enable $app.service --quiet
 
+#=================================================
+# RESTORE THE LOGROTATE CONFIGURATION
+#=================================================
+ynh_script_progression --message="Restoring the logrotate configuration..."
+
+ynh_restore_file --origin_path="/etc/logrotate.d/$app"
+
+set_permissions
+
 #=================================================
 # INTEGRATE SERVICE IN YUNOHOST
 #=================================================
@@ -138,20 +132,6 @@ ynh_script_progression --message="Starting a systemd service..." --weight=1
 
 ynh_systemd_action --service_name=$app --action="start" --log_path="/var/log/$app/$app.log"
 
-#=================================================
-# RESTORE VARIOUS FILES
-#=================================================
-
-ynh_restore_file --origin_path="/var/log/$app"
-
-#=================================================
-# RESTORE THE LOGROTATE CONFIGURATION
-#=================================================
-
-ynh_restore_file --origin_path="/etc/logrotate.d/$app"
-
-set_permissions
-
 #=================================================
 # GENERIC FINALIZATION
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 8f98769..0c5ecb2 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -29,6 +29,7 @@ mapbox_token=$(ynh_app_setting_get --app=$app --key=mapbox_token)
 #=================================================
 # CHECK VERSION
 #=================================================
+ynh_script_progression --message="Checking version..."
 
 upgrade_type=$(ynh_check_app_version_changed)
 
@@ -39,7 +40,8 @@ ynh_script_progression --message="Backing up the app before upgrading (may take
 
 # Backup the current version of the app
 ynh_backup_before_upgrade
-ynh_clean_setup() {
+ynh_clean_setup () {
+	ynh_clean_check_starting
 	# Restore it if the upgrade fails
 	ynh_restore_upgradebackup
 }
@@ -55,6 +57,18 @@ ynh_script_progression --message="Stopping a systemd service..." --weight=1
 
 ynh_systemd_action --service_name=$app --action="stop" --log_path="/var/log/$app/$app.log"
 
+#=================================================
+# ENSURE DOWNWARD COMPATIBILITY
+#=================================================
+ynh_script_progression --message="Ensuring downward compatibility..."
+
+# Cleaning legacy permissions
+if ynh_legacy_permissions_exists; then
+	ynh_legacy_permissions_delete_all
+
+	ynh_app_setting_delete --app=$app --key=is_public
+fi
+
 #=================================================
 # CREATE DEDICATED USER
 #=================================================
@@ -63,13 +77,6 @@ ynh_script_progression --message="Making sure dedicated system user exists..." -
 # Create a dedicated user (if not existing)
 ynh_system_user_create --username=$app --home_dir="$final_path"
 
-#=================================================
-# UPGRADE DEPENDENCIES
-#=================================================
-ynh_script_progression --message="Upgrading dependencies..." --weight=1
-
-install_dependencies
-
 #=================================================
 # DOWNLOAD, CHECK AND UNPACK SOURCE
 #=================================================
@@ -88,9 +95,18 @@ ynh_script_progression --message="Upgrading NGINX web server configuration..." -
 # Create a dedicated NGINX config
 ynh_add_nginx_config
 
+#=================================================
+# UPGRADE DEPENDENCIES
+#=================================================
+ynh_script_progression --message="Upgrading dependencies..." --weight=1
+
+install_dependencies
+
 #=================================================
 # SPECIFIC UPGRADE
 #=================================================
+# BUILD APP
+#=================================================
 
 if [ "$upgrade_type" == "UPGRADE_APP" ]; then
 	#=================================================
@@ -121,11 +137,12 @@ fi
 ynh_script_progression --message="Upgrading systemd configuration..." --weight=1
 
 # Create a dedicated systemd config
-ynh_add_systemd_config --service=$app
+ynh_add_systemd_config
 
 #=================================================
 # UPDATE A CONFIG FILE
 #=================================================
+ynh_script_progression --message="Updating a configuration file..."
 
 ynh_add_config --template=".env" --destination="$final_path/output/.env"
 
diff --git a/sources/extra_files/app/.gitignore b/sources/extra_files/app/.gitignore
deleted file mode 100644
index 783a4ae..0000000
--- a/sources/extra_files/app/.gitignore
+++ /dev/null
@@ -1,2 +0,0 @@
-*~
-*.sw[op]
diff --git a/sources/patches/.gitignore b/sources/patches/.gitignore
deleted file mode 100644
index 783a4ae..0000000
--- a/sources/patches/.gitignore
+++ /dev/null
@@ -1,2 +0,0 @@
-*~
-*.sw[op]