diff --git a/ChangeLog b/ChangeLog
index 7766fc58f58..5a045136113 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,26 @@ English Dolibarr ChangeLog
 --------------------------------------------------------------
 
 
+***** ChangeLog for 19.0.0 compared to 18.0.0 *****
+
+For users:
+----------
+NEW: Compatibility with PHP 8.3
+...
+
+For developers or integrators:
+------------------------------
+...
+
+WARNING:
+--------
+
+The following changes may create regressions for some external modules, but were necessary to make Dolibarr better:
+* More class properties (with old name in french) are now deprecated in favor of the property name in english.
+* Some API HTTP return code were moved from 401 to 403 to better follow REST specification.
+
+
+
 ***** ChangeLog for 19.0.0 compared to 18.0.0 *****
 
 For users:
diff --git a/htdocs/fourn/class/api_supplier_invoices.class.php b/htdocs/fourn/class/api_supplier_invoices.class.php
index 112f4bb1439..2c6251a1249 100644
--- a/htdocs/fourn/class/api_supplier_invoices.class.php
+++ b/htdocs/fourn/class/api_supplier_invoices.class.php
@@ -61,12 +61,17 @@ class SupplierInvoices extends DolibarrApi
 	 * @param	int		$id				ID of supplier invoice
 	 * @return  Object					Object with cleaned properties
 	 *
-	 * @throws	RestException
+	 * @throws 	RestException 403
+	 * @throws 	RestException 404
 	 */
 	public function get($id)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "lire")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -74,10 +79,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		$this->invoice->fetchObjectLinked();
 		return $this->_cleanObjectDatas($this->invoice);
 	}
@@ -101,10 +102,8 @@ class SupplierInvoices extends DolibarrApi
 	 */
 	public function index($sortfield = "t.rowid", $sortorder = 'ASC', $limit = 100, $page = 0, $thirdparty_ids = '', $status = '', $sqlfilters = '', $properties = '')
 	{
-		global $db;
-
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "lire")) {
-			throw new RestException(401);
+			throw new RestException(403);
 		}
 
 		$obj_ret = array();
@@ -196,13 +195,13 @@ class SupplierInvoices extends DolibarrApi
 	 *
 	 * @return int  ID of supplier invoice
 	 *
-	 * @throws RestException 401
+	 * @throws RestException 403
 	 * @throws RestException 500	System error
 	 */
 	public function post($request_data = null)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401, "Insuffisant rights");
+			throw new RestException(403, "Insuffisant rights");
 		}
 		// Check mandatory fields
 		$result = $this->_validate($request_data);
@@ -234,13 +233,17 @@ class SupplierInvoices extends DolibarrApi
 	 *
 	 * @return int
 	 *
-	 * @throws RestException 401
+	 * @throws RestException 403
 	 * @throws RestException 404
 	 */
 	public function put($id, $request_data = null)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -248,10 +251,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		foreach ($request_data as $field => $value) {
 			if ($field == 'id') {
 				continue;
@@ -279,24 +278,23 @@ class SupplierInvoices extends DolibarrApi
 	 *
 	 * @return array
 	 *
-	 * @throws RestException 401
+	 * @throws RestException 403
 	 * @throws RestException 404
 	 * @throws RestException 500	System error
 	 */
 	public function delete($id)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "supprimer")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 		$result = $this->invoice->fetch($id);
 		if (!$result) {
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		if ($this->invoice->delete(DolibarrApiAccess::$user) < 0) {
 			throw new RestException(500, 'Error when deleting invoice');
 		}
@@ -321,7 +319,7 @@ class SupplierInvoices extends DolibarrApi
 	 * @return  array
 	 *
 	 * @throws RestException 304
-	 * @throws RestException 401
+	 * @throws RestException 403
 	 * @throws RestException 404
 	 * @throws RestException 405
 	 * @throws RestException 500	System error
@@ -329,17 +327,18 @@ class SupplierInvoices extends DolibarrApi
 	public function validate($id, $idwarehouse = 0, $notrigger = 0)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401);
+			throw new RestException(403);
 		}
+
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
+		}
+
 		$result = $this->invoice->fetch($id);
 		if (!$result) {
 			throw new RestException(404, 'Invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		$result = $this->invoice->validate(DolibarrApiAccess::$user, '', $idwarehouse, $notrigger);
 		if ($result == 0) {
 			throw new RestException(304, 'Error nothing done. The invoice is already validated');
@@ -365,28 +364,28 @@ class SupplierInvoices extends DolibarrApi
 	 *
 	 * @return array
 	 * @throws RestException 400
-	 * @throws RestException 401
+	 * @throws RestException 403
 	 * @throws RestException 404
 	 * @throws RestException 405
 	 */
 	public function getPayments($id)
 	{
-		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "lire")) {
-			throw new RestException(401);
-		}
 		if (empty($id)) {
 			throw new RestException(400, 'Invoice ID is mandatory');
 		}
 
+		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "lire")) {
+			throw new RestException(403);
+		}
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
+		}
+
 		$result = $this->invoice->fetch($id);
 		if (!$result) {
 			throw new RestException(404, 'Invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
-		}
-
 		$result = $this->invoice->getListOfPayments();
 		if ($result < 0) {
 			throw new RestException(405, $this->invoice->error);
@@ -413,19 +412,22 @@ class SupplierInvoices extends DolibarrApi
 	 * @url     POST {id}/payments
 	 *
 	 * @return int  Payment ID
+	 *
 	 * @throws RestException 400
-	 * @throws RestException 401
+	 * @throws RestException 403
 	 * @throws RestException 404
 	 */
 	public function addPayment($id, $datepaye, $payment_mode_id, $closepaidinvoices, $accountid, $num_payment = '', $comment = '', $chqemetteur = '', $chqbank = '', $amount = null)
 	{
-		global $conf;
+		if (empty($id)) {
+			throw new RestException(400, 'Invoice ID is mandatory');
+		}
 
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
 			throw new RestException(403);
 		}
-		if (empty($id)) {
-			throw new RestException(400, 'Invoice ID is mandatory');
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -433,10 +435,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		if (isModEnabled("banque")) {
 			if (empty($accountid)) {
 				throw new RestException(400, 'Bank account ID is mandatory');
@@ -507,11 +505,17 @@ class SupplierInvoices extends DolibarrApi
 	 * @url	GET {id}/lines
 	 *
 	 * @return array
+	 *
+	 * @throws RestException 403
+	 * @throws RestException 404
 	 */
 	public function getLines($id)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -519,9 +523,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
 		$this->invoice->fetch_lines();
 		$result = array();
 		foreach ($this->invoice->lines as $line) {
@@ -543,11 +544,18 @@ class SupplierInvoices extends DolibarrApi
 	 * @url	POST {id}/lines
 	 *
 	 * @return int|bool
+	 *
+	 * @throws RestException 403
+	 * @throws RestException 404
 	 */
 	public function postLine($id, $request_data = null)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -555,10 +563,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		$request_data = (object) $request_data;
 
 		$request_data->description = sanitizeVal($request_data->description, 'restricthtml');
@@ -607,14 +611,18 @@ class SupplierInvoices extends DolibarrApi
 	 *
 	 * @return object
 	 *
-	 * @throws RestException 401 Not allowed
+	 * @throws RestException 403 Not allowed
 	 * @throws RestException 404 Not found
 	 * @throws RestException 304 Error
 	 */
 	public function putLine($id, $lineid, $request_data = null)
 	{
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -622,10 +630,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		$request_data = (object) $request_data;
 
 		$request_data->description = sanitizeVal($request_data->description, 'restricthtml');
@@ -674,14 +678,21 @@ class SupplierInvoices extends DolibarrApi
 	 * @return array
 	 *
 	 * @throws RestException 400 Bad parameters
-	 * @throws RestException 401 Not allowed
+	 * @throws RestException 403 Not allowed
 	 * @throws RestException 404 Not found
 	 * @throws RestException 405 Error
 	 */
 	public function deleteLine($id, $lineid)
 	{
+		if (empty($lineid)) {
+			throw new RestException(400, 'Line ID is mandatory');
+		}
+
 		if (!DolibarrApiAccess::$user->hasRight("fournisseur", "facture", "creer")) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+		if (!DolibarrApi::_checkAccessToResource('fournisseur', $id, 'facture_fourn', 'facture')) {
+			throw new RestException(403, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->invoice->fetch($id);
@@ -689,14 +700,6 @@ class SupplierInvoices extends DolibarrApi
 			throw new RestException(404, 'Supplier invoice not found');
 		}
 
-		if (empty($lineid)) {
-			throw new RestException(400, 'Line ID is mandatory');
-		}
-
-		if (!DolibarrApi::_checkAccessToResource('fournisseur', $this->invoice->id, 'facture_fourn', 'facture')) {
-			throw new RestException(401, 'Access not allowed for login ' . DolibarrApiAccess::$user->login);
-		}
-
 		// TODO Check the lineid $lineid is a line of object
 
 		$updateRes = $this->invoice->deleteline($lineid);
diff --git a/htdocs/modulebuilder/template/class/api_mymodule.class.php b/htdocs/modulebuilder/template/class/api_mymodule.class.php
index 25a086f58cd..42c8d9874ba 100644
--- a/htdocs/modulebuilder/template/class/api_mymodule.class.php
+++ b/htdocs/modulebuilder/template/class/api_mymodule.class.php
@@ -66,13 +66,16 @@ class MyModuleApi extends DolibarrApi
 	 *
 	 * @url	GET myobjects/{id}
 	 *
-	 * @throws RestException 401 Not allowed
+	 * @throws RestException 403 Not allowed
 	 * @throws RestException 404 Not found
 	 */
 	public function get($id)
 	{
 		if (!DolibarrApiAccess::$user->rights->mymodule->myobject->read) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+		if (!DolibarrApi::_checkAccessToResource('myobject', $id, 'mymodule_myobject')) {
+			throw new RestException(403, 'Access to instance id='.$this->myobject->id.' of object not allowed for login '.DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->myobject->fetch($id);
@@ -80,10 +83,6 @@ class MyModuleApi extends DolibarrApi
 			throw new RestException(404, 'MyObject not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('myobject', $this->myobject->id, 'mymodule_myobject')) {
-			throw new RestException(401, 'Access to instance id='.$this->myobject->id.' of object not allowed for login '.DolibarrApiAccess::$user->login);
-		}
-
 		return $this->_cleanObjectDatas($this->myobject);
 	}
 
@@ -101,7 +100,8 @@ class MyModuleApi extends DolibarrApi
 	 * @param string		   $properties			Restrict the data returned to these properties. Ignored if empty. Comma separated list of properties names
 	 * @return  array                               Array of order objects
 	 *
-	 * @throws RestException
+	 * @throws RestException 403 Not allowed
+	 * @throws RestException 503 System error
 	 *
 	 * @url	GET /myobjects/
 	 */
@@ -111,7 +111,7 @@ class MyModuleApi extends DolibarrApi
 		$tmpobject = new MyObject($this->db);
 
 		if (!DolibarrApiAccess::$user->rights->mymodule->myobject->read) {
-			throw new RestException(401);
+			throw new RestException(403);
 		}
 
 		$socid = DolibarrApiAccess::$user->socid ? DolibarrApiAccess::$user->socid : 0;
@@ -186,16 +186,17 @@ class MyModuleApi extends DolibarrApi
 	 * Create myobject object
 	 *
 	 * @param array $request_data   Request datas
-	 * @return int  ID of myobject
+	 * @return int  				ID of myobject
 	 *
-	 * @throws RestException
+	 * @throws RestException 403 Not allowed
+	 * @throws RestException 500 System error
 	 *
 	 * @url	POST myobjects/
 	 */
 	public function post($request_data = null)
 	{
 		if (!DolibarrApiAccess::$user->rights->mymodule->myobject->write) {
-			throw new RestException(401);
+			throw new RestException(403);
 		}
 
 		// Check mandatory fields
@@ -227,14 +228,19 @@ class MyModuleApi extends DolibarrApi
 	 * @param array $request_data   Datas
 	 * @return int
 	 *
-	 * @throws RestException
+	 * @throws RestException 403 Not allowed
+	 * @throws RestException 404 Not found
+	 * @throws RestException 500 System error
 	 *
 	 * @url	PUT myobjects/{id}
 	 */
 	public function put($id, $request_data = null)
 	{
 		if (!DolibarrApiAccess::$user->rights->mymodule->myobject->write) {
-			throw new RestException(401);
+			throw new RestException(403);
+		}
+		if (!DolibarrApi::_checkAccessToResource('myobject', $id, 'mymodule_myobject')) {
+			throw new RestException(403, 'Access to instance id='.$this->myobject->id.' of object not allowed for login '.DolibarrApiAccess::$user->login);
 		}
 
 		$result = $this->myobject->fetch($id);
@@ -242,10 +248,6 @@ class MyModuleApi extends DolibarrApi
 			throw new RestException(404, 'MyObject not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('myobject', $this->myobject->id, 'mymodule_myobject')) {
-			throw new RestException(401, 'Access to instance id='.$this->myobject->id.' of object not allowed for login '.DolibarrApiAccess::$user->login);
-		}
-
 		foreach ($request_data as $field => $value) {
 			if ($field == 'id') {
 				continue;
@@ -275,24 +277,27 @@ class MyModuleApi extends DolibarrApi
 	 * @param   int     $id   MyObject ID
 	 * @return  array
 	 *
-	 * @throws RestException
+	 * @throws RestException 403 Not allowed
+	 * @throws RestException 404 Not found
+	 * @throws RestException 409 Nothing to do
+	 * @throws RestException 500 System error
 	 *
 	 * @url	DELETE myobjects/{id}
 	 */
 	public function delete($id)
 	{
-		if (!DolibarrApiAccess::$user->rights->mymodule->myobject->delete) {
-			throw new RestException(401);
+		if (!DolibarrApiAccess::$user->hasRight('mymodule', 'myobject', 'delete')) {
+			throw new RestException(403);
 		}
+		if (!DolibarrApi::_checkAccessToResource('myobject', $id, 'mymodule_myobject')) {
+			throw new RestException(403, 'Access to instance id='.$this->myobject->id.' of object not allowed for login '.DolibarrApiAccess::$user->login);
+		}
+
 		$result = $this->myobject->fetch($id);
 		if (!$result) {
 			throw new RestException(404, 'MyObject not found');
 		}
 
-		if (!DolibarrApi::_checkAccessToResource('myobject', $this->myobject->id, 'mymodule_myobject')) {
-			throw new RestException(401, 'Access to instance id='.$this->myobject->id.' of object not allowed for login '.DolibarrApiAccess::$user->login);
-		}
-
 		if ($this->myobject->delete(DolibarrApiAccess::$user) == 0) {
 			throw new RestException(409, 'Error when deleting MyObject : '.$this->myobject->error);
 		} elseif ($this->myobject->delete(DolibarrApiAccess::$user) < 0) {
@@ -348,40 +353,6 @@ class MyModuleApi extends DolibarrApi
 		unset($object->rowid);
 		unset($object->canvas);
 
-		/*unset($object->name);
-		unset($object->lastname);
-		unset($object->firstname);
-		unset($object->civility_id);
-		unset($object->statut);
-		unset($object->state);
-		unset($object->state_id);
-		unset($object->state_code);
-		unset($object->region);
-		unset($object->region_code);
-		unset($object->country);
-		unset($object->country_id);
-		unset($object->country_code);
-		unset($object->barcode_type);
-		unset($object->barcode_type_code);
-		unset($object->barcode_type_label);
-		unset($object->barcode_type_coder);
-		unset($object->total_ht);
-		unset($object->total_tva);
-		unset($object->total_localtax1);
-		unset($object->total_localtax2);
-		unset($object->total_ttc);
-		unset($object->fk_account);
-		unset($object->comments);
-		unset($object->note);
-		unset($object->mode_reglement_id);
-		unset($object->cond_reglement_id);
-		unset($object->cond_reglement);
-		unset($object->shipping_method_id);
-		unset($object->fk_incoterms);
-		unset($object->label_incoterms);
-		unset($object->location_incoterms);
-		*/
-
 		// If object has lines, remove $db property
 		if (isset($object->lines) && is_array($object->lines) && count($object->lines) > 0) {
 			$nboflines = count($object->lines);