diff --git a/htdocs/core/class/conf.class.php b/htdocs/core/class/conf.class.php
index 94611852d22f0..711a0bb499ded 100644
--- a/htdocs/core/class/conf.class.php
+++ b/htdocs/core/class/conf.class.php
@@ -4,6 +4,7 @@
  * Copyright (C) 2004-2020 Laurent Destailleur  <eldy@users.sourceforge.net>
  * Copyright (C) 2005-2017 Regis Houssin      	<regis.houssin@inodbox.com>
  * Copyright (C) 2006 	   Jean Heimburger    	<jean@tiaris.info>
+ * Copyright (C) 2024		MDW							<mdeweerd@users.noreply.github.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -19,6 +20,7 @@
  * along with this program. If not, see <https://www.gnu.org/licenses/>.
  */
 
+require_once DOL_DOCUMENT_ROOT.'/core/class/doldeprecationhandler.class.php';
 
 /**
  *	\file       	htdocs/core/class/conf.class.php
@@ -29,9 +31,17 @@
 
 /**
  *  Class to stock current configuration
+ *
  */
 class Conf extends stdClass
 {
+	use DolDeprecationHandler;
+	/**
+	 * When true, indicates to the DeprecationHandler that this
+	 * class supports dynamic properties.
+	 */
+	protected $enableDynamicProperties = true;
+
 	/**
 	 * @var Object 	Associative array with properties found in conf file
 	 */
@@ -85,7 +95,6 @@ class Conf extends stdClass
 
 	//! Used to store current menu handler
 	public $standard_menu;
-
 	/**
 	 * @var array<string,string>  List of activated modules
 	 */
@@ -154,53 +163,173 @@ class Conf extends stdClass
 	public $fournisseur;
 
 	/**
-	 * @var stdClass	Product
+	 * @var stdClass
 	 */
 	public $product;
 
 	/**
-	 * @deprecated Use product
+	 * @var stdClass
+	 * @deprecated      Use $product
+	 * @see $product
+	 */
+	private $produit;
+
+	/**
+	 * @var stdClass
 	 */
-	public $produit;
 	public $service;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $contract
+	 * @see $contract
+	 */
+	private $contrat;
+
 	/**
-	 * @deprecated Use contract
+	 * @var stdClass
 	 */
-	public $contrat;
 	public $contract;
+
+	/**
+	 * @var stdClass
+	 */
 	public $actions;
+
+	/**
+	 * @var stdClass
+	 */
 	public $agenda;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $order
+	 * @see $order
+	 */
+	private $commande;
+
+	/**
+	 * @var stdClass
+	 */
 	public $propal;
+
 	/**
-	 * @deprecated Use order
+	 * @var stdClass
 	 */
-	public $commande;
 	public $order;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $invoice
+	 * @see $invoice
+	 */
+	private $facture;
+
+
 	/**
-	 * @deprecated Use invoice
+	 * @var stdClass
 	 */
-	public $facture;
 	public $invoice;
+
+	/**
+	 * @var stdClass
+	 */
 	public $user;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $member
+	 * @see $member
+	 */
+	private $adherent;
+
+
 	/**
-	 * @deprecated Use member
+	 * @var stdClass
 	 */
-	public $adherent;
 	public $member;
+
+	/**
+	 * @var stdClass
+	 */
 	public $bank;
+
+	/**
+	 * @var stdClass
+	 */
 	public $notification;
+
+	/**
+	 * @var stdClass
+	 */
 	public $expensereport;
+
+	/**
+	 * @var stdClass
+	 */
 	public $productbatch;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $project
+	 * @see $project
+	 */
+	private $projet;
+
+
 	/**
-	 * @deprecated Use project
+	 * @var stdClass
 	 */
-	public $projet;
 	public $project;
+
+	/**
+	 * @var stdClass
+	 */
 	public $supplier_proposal;
+
+	/**
+	 * @var stdClass
+	 */
 	public $supplier_order;
+
+	/**
+	 * @var stdClass
+	 */
 	public $supplier_invoice;
+
+	/**
+	 * @var stdClass
+	 */
 	public $category;
 
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $category
+	 * @see $category
+	 */
+	private $categorie;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $supplier_proposal
+	 * @see $supplier_proposal
+	 */
+	private $supplierproposal;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $delivery_note
+	 * @see $delivery_note
+	 */
+	private $expedition;
+
+	/**
+	 * @var stdClass
+	 * @deprecated      Use $bank
+	 * @see $bank
+	 */
+	private $banque;
+
 
 	/**
 	 * Constructor
@@ -252,20 +381,45 @@ public function __construct()
 		$this->fournisseur = new stdClass();
 		$this->product = new stdClass();
 		$this->service = new stdClass();
-		$this->contrat = new stdClass();
+		$this->contract = new stdClass();
 		$this->actions = new stdClass();
 		$this->agenda = new stdClass();
-		$this->commande = new stdClass();
+		$this->order = new stdClass();
 		$this->propal = new stdClass();
-		$this->facture = new stdClass();
+		$this->invoice = new stdClass();
 		$this->user	= new stdClass();
-		$this->adherent = new stdClass();
+		$this->member = new stdClass();
 		$this->bank = new stdClass();
 		$this->notification = new stdClass();
 		$this->expensereport = new stdClass();
 		$this->productbatch = new stdClass();
 	}
 
+	/**
+	 * Provide list of deprecated properties and replacements
+	 *
+	 * @return array<string,string>
+	 */
+	protected function deprecatedProperties()
+	{
+		return MODULE_MAPPING
+		+ array(
+			// Previously detected module names, already in mapping
+			//'adherent' => 'member',
+			//'banque' => 'bank',
+			//'categorie' => 'category',
+			//'commande' => 'order',
+			//'contrat' => 'contract',
+			//'expedition' => 'delivery_note',
+			//'facture' => 'invoice',
+			//'projet' => 'project',
+
+			// Other, not deprecated module names
+			'produit' => 'product',
+			'supplierproposal' => 'supplier_proposal',
+		);
+	}
+
 
 	/**
 	 * Load setup values into conf object (read llx_const) for a specified entity
@@ -320,14 +474,14 @@ public function setValues($db)
 		$this->fournisseur = new stdClass();
 		$this->product = new stdClass();
 		$this->service = new stdClass();
-		$this->contrat = new stdClass();
+		$this->contract = new stdClass();
 		$this->actions = new stdClass();
 		$this->agenda = new stdClass();
-		$this->commande = new stdClass();
+		$this->order = new stdClass();
 		$this->propal = new stdClass();
-		$this->facture = new stdClass();
+		$this->invoice = new stdClass();
 		$this->user	= new stdClass();
-		$this->adherent = new stdClass();
+		$this->member = new stdClass();
 		$this->bank = new stdClass();
 		$this->notification = new stdClass();
 		$this->expensereport = new stdClass();
@@ -428,12 +582,6 @@ public function setValues($db)
 							} elseif (preg_match('/^MAIN_MODULE_([0-9A-Z_]+)$/i', $key, $reg)) {
 								// If this is a module constant (must be at end)
 								$modulename = strtolower($reg[1]);
-								if ($modulename == 'propale') {
-									$modulename = 'propal';
-								}
-								if ($modulename == 'supplierproposal') {
-									$modulename = 'supplier_proposal';
-								}
 								$this->modules[$modulename] = $modulename; // Add this module in list of enabled modules
 
 								// deprecated in php 8.2
@@ -444,7 +592,6 @@ public function setValues($db)
 								$this->$modulename->enabled = true;	// TODO Remove this
 
 								// Duplicate entry with the new name
-								/*
 								$mapping = $this->deprecatedProperties();
 								if (array_key_exists($modulename, $mapping)) {
 									$newmodulename = $mapping[$modulename];
@@ -455,7 +602,6 @@ public function setValues($db)
 									}
 									$this->$newmodulename->enabled = true;	// TODO Remove this
 								}
-								*/
 							}
 						}
 					}
@@ -675,12 +821,12 @@ public function setValues($db)
 			$this->productbatch->multidir_output = array($this->entity => $rootfordata."/productlot");
 			$this->productbatch->multidir_temp = array($this->entity => $rootfortemp."/productlot/temp");
 
-			// Module contrat
-			$this->contrat->multidir_output = array($this->entity => $rootfordata."/contract");
-			$this->contrat->multidir_temp = array($this->entity => $rootfortemp."/contract/temp");
+			// Module contract
+			$this->contract->multidir_output = array($this->entity => $rootfordata."/contract");
+			$this->contract->multidir_temp = array($this->entity => $rootfortemp."/contract/temp");
 			// For backward compatibility
-			$this->contrat->dir_output = $rootfordata."/contract";
-			$this->contrat->dir_temp = $rootfortemp."/contract/temp";
+			$this->contract->dir_output = $rootfordata."/contract";
+			$this->contract->dir_temp = $rootfortemp."/contract/temp";
 
 			// Module bank
 			$this->bank->multidir_output = array($this->entity => $rootfordata."/bank");
@@ -963,23 +1109,23 @@ public function setValues($db)
 			// Delay before warnings
 			// Avoid strict errors. TODO: Replace xxx->warning_delay with a property ->warning_delay_xxx
 			if (isset($this->agenda)) {
-				$this->adherent->subscription = new stdClass();
-				$this->adherent->subscription->warning_delay = (isset($this->global->MAIN_DELAY_MEMBERS) ? (int) $this->global->MAIN_DELAY_MEMBERS : 0) * 86400;
+				$this->member->subscription = new stdClass();
+				$this->member->subscription->warning_delay = (isset($this->global->MAIN_DELAY_MEMBERS) ? (int) $this->global->MAIN_DELAY_MEMBERS : 0) * 86400;
 			}
 			if (isset($this->agenda)) {
 				$this->agenda->warning_delay = (isset($this->global->MAIN_DELAY_ACTIONS_TODO) ? (int) $this->global->MAIN_DELAY_ACTIONS_TODO : 7) * 86400;
 			}
-			if (isset($this->projet)) {
-				$this->projet->warning_delay = (getDolGlobalInt('MAIN_DELAY_PROJECT_TO_CLOSE', 7) * 86400);
-				$this->projet->task = new StdClass();
-				$this->projet->task->warning_delay = (getDolGlobalInt('MAIN_DELAY_TASKS_TODO', 7) * 86400);
+			if (isset($this->project)) {
+				$this->project->warning_delay = (getDolGlobalInt('MAIN_DELAY_PROJECT_TO_CLOSE', 7) * 86400);
+				$this->project->task = new StdClass();
+				$this->project->task->warning_delay = (getDolGlobalInt('MAIN_DELAY_TASKS_TODO', 7) * 86400);
 			}
 
-			if (isset($this->commande)) {
-				$this->commande->client = new stdClass();
-				$this->commande->fournisseur = new stdClass();
-				$this->commande->client->warning_delay = (isset($this->global->MAIN_DELAY_ORDERS_TO_PROCESS) ? (int) $this->global->MAIN_DELAY_ORDERS_TO_PROCESS : 2) * 86400;
-				$this->commande->fournisseur->warning_delay = (isset($this->global->MAIN_DELAY_SUPPLIER_ORDERS_TO_PROCESS) ? (int) $this->global->MAIN_DELAY_SUPPLIER_ORDERS_TO_PROCESS : 7) * 86400;
+			if (isset($this->order)) {
+				$this->order->client = new stdClass();
+				$this->order->fournisseur = new stdClass();
+				$this->order->client->warning_delay = (isset($this->global->MAIN_DELAY_ORDERS_TO_PROCESS) ? (int) $this->global->MAIN_DELAY_ORDERS_TO_PROCESS : 2) * 86400;
+				$this->order->fournisseur->warning_delay = (isset($this->global->MAIN_DELAY_SUPPLIER_ORDERS_TO_PROCESS) ? (int) $this->global->MAIN_DELAY_SUPPLIER_ORDERS_TO_PROCESS : 7) * 86400;
 			}
 			if (isset($this->propal)) {
 				$this->propal->cloture = new stdClass();
@@ -987,20 +1133,20 @@ public function setValues($db)
 				$this->propal->cloture->warning_delay = (isset($this->global->MAIN_DELAY_PROPALS_TO_CLOSE) ? (int) $this->global->MAIN_DELAY_PROPALS_TO_CLOSE : 0) * 86400;
 				$this->propal->facturation->warning_delay = (isset($this->global->MAIN_DELAY_PROPALS_TO_BILL) ? (int) $this->global->MAIN_DELAY_PROPALS_TO_BILL : 0) * 86400;
 			}
-			if (isset($this->facture)) {
-				$this->facture->client = new stdClass();
-				$this->facture->fournisseur = new stdClass();
-				$this->facture->client->warning_delay = (isset($this->global->MAIN_DELAY_CUSTOMER_BILLS_UNPAYED) ? (int) $this->global->MAIN_DELAY_CUSTOMER_BILLS_UNPAYED : 0) * 86400;
-				$this->facture->fournisseur->warning_delay = (isset($this->global->MAIN_DELAY_SUPPLIER_BILLS_TO_PAY) ? (int) $this->global->MAIN_DELAY_SUPPLIER_BILLS_TO_PAY : 0) * 86400;
+			if (isset($this->invoice)) {
+				$this->invoice->client = new stdClass();
+				$this->invoice->fournisseur = new stdClass();
+				$this->invoice->client->warning_delay = (isset($this->global->MAIN_DELAY_CUSTOMER_BILLS_UNPAYED) ? (int) $this->global->MAIN_DELAY_CUSTOMER_BILLS_UNPAYED : 0) * 86400;
+				$this->invoice->fournisseur->warning_delay = (isset($this->global->MAIN_DELAY_SUPPLIER_BILLS_TO_PAY) ? (int) $this->global->MAIN_DELAY_SUPPLIER_BILLS_TO_PAY : 0) * 86400;
 			}
-			if (isset($this->contrat)) {
-				$this->contrat->services = new stdClass();
-				$this->contrat->services->inactifs = new stdClass();
-				$this->contrat->services->expires = new stdClass();
-				$this->contrat->services->inactifs->warning_delay = (isset($this->global->MAIN_DELAY_NOT_ACTIVATED_SERVICES) ? (int) $this->global->MAIN_DELAY_NOT_ACTIVATED_SERVICES : 0) * 86400;
-				$this->contrat->services->expires->warning_delay = (isset($this->global->MAIN_DELAY_RUNNING_SERVICES) ? (int) $this->global->MAIN_DELAY_RUNNING_SERVICES : 0) * 86400;
+			if (isset($this->contract)) {
+				$this->contract->services = new stdClass();
+				$this->contract->services->inactifs = new stdClass();
+				$this->contract->services->expires = new stdClass();
+				$this->contract->services->inactifs->warning_delay = (isset($this->global->MAIN_DELAY_NOT_ACTIVATED_SERVICES) ? (int) $this->global->MAIN_DELAY_NOT_ACTIVATED_SERVICES : 0) * 86400;
+				$this->contract->services->expires->warning_delay = (isset($this->global->MAIN_DELAY_RUNNING_SERVICES) ? (int) $this->global->MAIN_DELAY_RUNNING_SERVICES : 0) * 86400;
 			}
-			if (isset($this->commande)) {
+			if (isset($this->order)) {
 				$this->bank->rappro	= new stdClass();
 				$this->bank->cheque	= new stdClass();
 				$this->bank->rappro->warning_delay = (isset($this->global->MAIN_DELAY_TRANSACTIONS_TO_CONCILIATE) ? (int) $this->global->MAIN_DELAY_TRANSACTIONS_TO_CONCILIATE : 0) * 86400;
@@ -1102,37 +1248,6 @@ public function setValues($db)
 				unset($this->global->MAIN_NO_CONCAT_DESCRIPTION);
 			}
 
-			// Simple deprecation management. We do not use DolDeprecationHandlet for $conf.
-
-			// product is new use
-			if (isset($this->product)) {
-				// For backward compatibility
-				$this->produit = $this->product;
-			}
-			// invoice is new use, facture is old use still initialised
-			if (isset($this->facture)) {
-				$this->invoice = $this->facture;
-			}
-			// order is new use, commande is old use still initialised
-			if (isset($this->commande)) {
-				$this->order = $this->commande;
-			}
-			// contract is new use, contrat is old use still initialised
-			if (isset($this->contrat)) {
-				$this->contract = $this->contrat;
-			}
-			// category is new use, categorie is old use still initialised
-			if (isset($this->categorie)) {
-				$this->category = $this->categorie;
-			}
-			// project is new use, projet is old use still initialised
-			if (isset($this->projet) && !isset($this->project)) {
-				$this->project = $this->projet;
-			}
-			// member is new use, adherent is old use still initialised
-			if (isset($this->adherent) && !isset($this->member)) {
-				$this->member = $this->adherent;
-			}
 
 			// Object $mc
 			if (!defined('NOREQUIREMC') && isModEnabled('multicompany')) {