diff --git a/scripts/install b/scripts/install
index 88c1c0d..0e30319 100755
--- a/scripts/install
+++ b/scripts/install
@@ -64,7 +64,8 @@ exec_occ() {
 }
 
 # Set write access for the following commands
-chown -R $app: "$install_dir" "$data_dir"
+find "$install_dir" -not \( -user $app -or -group www-data \) -exec chown $app:www-data {} \+
+find "$data_dir" -not \( -user $app -or -group $app \) -exec chown $app: {} \+
 
 # Define password in an intermediate var
 # The fact that it's called _password allows it to be
@@ -234,8 +235,8 @@ ynh_multimedia_addaccess $app
 #=================================================
 
 # Fix app ownerships & permissions
-chown -R $app:www-data "$install_dir"
-chown -R $app: "$data_dir"
+find "$install_dir" -not \( -user $app -or -group www-data \) -exec chown $app:www-data {} \+
+find "$data_dir" -not \( -user $app -or -group $app \) -exec chown $app: {} \+
 find $install_dir/ -type f -print0 | xargs -r0 chmod 0644
 find $install_dir/ -type d -print0 | xargs -r0 chmod 0755
 find $data_dir/data/ -type f -print0 | xargs -r0 chmod 0640
diff --git a/scripts/restore b/scripts/restore
index 1b0f63c..da7848e 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -79,8 +79,8 @@ ynh_restore_file --origin_path="$data_dir" --not_mandatory
 #=================================================
 
 # Fix app ownerships & permissions
-chown -R $app:www-data "$install_dir"
-chown -R $app: "$data_dir"
+find "$install_dir" -not \( -user $app -or -group www-data \) -exec chown $app:www-data {} \+
+find "$data_dir" -not \( -user $app -or -group $app \) -exec chown $app: {} \+
 find $install_dir/ -type f -print0 | xargs -r0 chmod 0644
 find $install_dir/ -type d -print0 | xargs -r0 chmod 0755
 find $data_dir/data/ -type f -print0 | xargs -r0 chmod 0640
diff --git a/scripts/upgrade b/scripts/upgrade
index e36d62e..5d70446 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -138,7 +138,8 @@ then
     ynh_script_progression --message="Upgrading $app..." --weight=3
 
     # Set write access for the following commands
-    chown -R $app: "$install_dir" "$data_dir"
+    find "$install_dir" -not \( -user $app -or -group www-data \) -exec chown $app:www-data {} \+
+    find "$data_dir" -not \( -user $app -or -group $app \) -exec chown $app: {} \+
 
     # Print the current version number of Nextcloud
     exec_occ -V
@@ -207,7 +208,8 @@ then
         mv "$tmpdir" "$install_dir"
 
         # Set write access for the following commands
-        chown -R $app: "$install_dir" "$data_dir"
+        find "$install_dir" -not \( -user $app -or -group www-data \) -exec chown $app:www-data {} \+
+        find "$data_dir" -not \( -user $app -or -group $app \) -exec chown $app: {} \+
 
         # Upgrade Nextcloud (SUCCESS = 0, UP_TO_DATE = 3)
         exec_occ maintenance:mode --off
@@ -324,8 +326,8 @@ fi
 ynh_script_progression --message="Reapplying file permissions..." --weight=2
 
 # Fix app ownerships & permissions
-chown -R $app:www-data "$install_dir"
-chown -R $app: "$data_dir"
+find "$install_dir" -not \( -user $app -or -group www-data \) -exec chown $app:www-data {} \+
+find "$data_dir" -not \( -user $app -or -group $app \) -exec chown $app: {} \+
 find $install_dir/ -type f -print0 | xargs -r0 chmod 0644
 find $install_dir/ -type d -print0 | xargs -r0 chmod 0755
 find $data_dir/data/ -type f -print0 | xargs -r0 chmod 0640