diff --git a/README.md b/README.md
index abf1f74..17b28b2 100644
--- a/README.md
+++ b/README.md
@@ -12,7 +12,7 @@ If you don't have YunoHost, please see [here](https://yunohost.org/#/install) to
 own data. A personal cloud which run on your own server. With Nextcloud
 you can synchronize your files over your devices.
 
-**Shipped version:** 16.0.1
+**Shipped version:** 17.0.0
 
 ## Screenshots
 
diff --git a/conf/php-fpm.conf b/conf/php-fpm.conf
index 1924bbe..33dcb5e 100644
--- a/conf/php-fpm.conf
+++ b/conf/php-fpm.conf
@@ -434,7 +434,10 @@ php_admin_value[memory_limit] = 512M
 php_value[upload_max_filesize] = 10G
 php_value[post_max_size] = 10G
 php_value[default_charset] = UTF-8
-php_value[opcache.enable]=1
+; OPcache is already activated by default
+; php_value[opcache.enable]=1
+; The following parameters are nevertheless recommended for Nextcloud
+; see here: https://docs.nextcloud.com/server/15/admin_manual/installation/server_tuning.html#enable-php-opcache
 php_value[opcache.enable_cli]=1
 php_value[opcache.interned_strings_buffer]=8
 php_value[opcache.max_accelerated_files]=10000
diff --git a/scripts/install b/scripts/install
index f713e22..e1fb3ba 100755
--- a/scripts/install
+++ b/scripts/install
@@ -71,7 +71,7 @@ ynh_mysql_setup_db --db_user=$db_name --db_name=$db_name
 #=================================================
 # DOWNLOAD, CHECK AND UNPACK SOURCE
 #=================================================
-ynh_script_progression --message="Setting up source files..."5
+ynh_script_progression --message="Setting up source files..."
 
 # Load the last available version
 source upgrade.d/upgrade.last.sh
diff --git a/scripts/upgrade b/scripts/upgrade
index 233616b..2c3c5a7 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -179,23 +179,34 @@ ynh_install_php --phpversion="$php_version" --package="$extra_pkg_dependencies"
 # VERSION TO THE NEXT ONE
 #=================================================
 
+# Define a function to execute commands with `occ`
+exec_occ() {
+(cd "$final_path" && exec_as "$app" \
+    php occ --no-interaction --no-ansi "$@")
+}
+
+# Define a function to add an external storage
+# Create the external storage for the given folders and enable sharing
+create_external_storage() {
+local datadir="$1"
+local mount_name="$2"
+local mount_id=`exec_occ files_external:create --output=json \
+    "$mount_name" 'local' 'null::null' -c "datadir=$datadir" || true`
+! [[ $mount_id =~ ^[0-9]+$ ]] \
+    && ynh_print_warn --message="Unable to create external storage" \
+    || exec_occ files_external:option "$mount_id" enable_sharing true
+}
+# Define app's data directory
+datadir="/home/yunohost.app/$app/data"
+
 if [ "$upgrade_type" == "UPGRADE_APP" ]
 then
     ynh_script_progression --message="Upgrading nextcloud..." --weight=3
 
-    # Define a function to execute commands with `occ`
-    exec_occ() {
-    (cd "$final_path" && exec_as "$app" \
-        php$php_version occ --no-interaction --no-ansi "$@")
-    }
-
     # Load the last available version
     source upgrade.d/upgrade.last.sh
     last_version=$next_version
 
-    # Define app's data directory
-    datadir="/home/yunohost.app/$app/data"
-
     # Set write access for the following commands
     chown -R $app: "$final_path" "$datadir"
 
@@ -244,7 +255,16 @@ then
         # Backup 3rd party applications from the current nextcloud
         # But do not overwrite if there is any upgrade
         # (apps directory already exists in Nextcloud archive)
-        cp -a --update "$final_path/apps" "$tmpdir"
+        (
+        cd $final_path/apps
+        for nc_app_dir in */
+        do
+          if [ ! -d "$tmpdir/apps/$nc_app_dir" ]
+          then
+            cp -a "$nc_app_dir" "$tmpdir/apps/$nc_app_dir"
+          fi
+        done
+        )
 
         # Replace the old nextcloud by the new one
         ynh_secure_remove --file="$final_path"
@@ -317,18 +337,6 @@ then
     # MOUNT HOME FOLDERS AS EXTERNAL STORAGE
     #=================================================
 
-    # Define a function to add an external storage
-    # Create the external storage for the given folders and enable sharing
-    create_external_storage() {
-    local datadir="$1"
-    local mount_name="$2"
-    local mount_id=`exec_occ files_external:create --output=json \
-        "$mount_name" 'local' 'null::null' -c "datadir=$datadir" || true`
-    ! [[ $mount_id =~ ^[0-9]+$ ]] \
-        && ynh_print_warn --message="Unable to create external storage" \
-        || exec_occ files_external:option "$mount_id" enable_sharing true
-    }
-
     # Enable External Storage and create local mount to home folder as needed
     if [ $user_home -eq 1 ]; then
         exec_occ app:enable files_external