diff --git a/ChangeLog b/ChangeLog
index fa94db352a0..790883386d4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -21,7 +21,7 @@ The following changes may create regressions for some external modules, but were
 * The use of GETPOST function is not allowed inside extrafields conditions or any strings that contains dynamic code evaluated with dol_eval().
 * The deprecated variable $trigger_name (duplicate of variable $triggersendname) has been removed. You must use $triggersendname everywhere now.
 * The behavior of constant STOCK_ALLOW_NEGATIVE_TRANSFER has been reversed. It has been renamed to STOCK_DISALLOW_NEGATIVE_TRANSFER.
-* Method Categoie->getObjectsInCateg() is deprecated. Try by using instead getListForItem().
+* Method Categoie->getObjectsInCateg() is deprecated. Try by using instead getListForItem() or containing().
 
 
 ***** ChangeLog for 21.0.0 compared to 20.0 *****
diff --git a/htdocs/categories/class/categorie.class.php b/htdocs/categories/class/categorie.class.php
index db948810753..31d692afab1 100644
--- a/htdocs/categories/class/categorie.class.php
+++ b/htdocs/categories/class/categorie.class.php
@@ -945,8 +945,8 @@ class Categorie extends CommonObject
 	}
 
 	/**
-	 * Return list of fetched instances of elements having this category
-	 * WARNING: Do not use this. It can return an array with a very high number of element making an out of memory. Try by using instead getListForItem().
+	 * Return list of fetched instances of elements having the current category.
+	 * WARNING: Do not use this. It can return an array with a very high number of element making an out of memory. Try by using instead getListForItem() or containing().
 	 *
 	 * @param   string     	$type       	Type of category ('customer', 'supplier', 'contact', 'product', 'member', 'knowledge_management', ...)
 	 * @param   int        	$onlyids    	Return only ids of objects (consume less memory)
@@ -961,13 +961,14 @@ class Categorie extends CommonObject
 	 * @param   string		$filterlang     Language to use in Universal Search for multilingual fields ('fr_FR', 'en_US'...)
 	 * @return  CommonObject[]|int[]|int    Return -1 if KO, array of instance of object if OK
 	 * @see containsObject()
-	 * @deprecated
 	 */
 	public function getObjectsInCateg($type, $onlyids = 0, $limit = 0, $offset = 0, $sortfield = '', $sortorder = 'ASC', $filter = '', $filtermode = 'AND', $filterlang = '')
 	{
 		global $user;
 
-		dol_syslog("getObjectsInCateg This method is deprecated. Try by using instead getListForItem().", LOG_WARNING);
+		if (empty($onlyids)) {
+			dol_syslog("getObjectsInCateg: This method used with parameter onlyids=0 is deprecated. Try by using instead getListForItem().", LOG_WARNING);
+		}
 
 		$objs = array();
 
@@ -1035,7 +1036,7 @@ class Categorie extends CommonObject
 	}
 
 	/**
-	 * Check for the presence of an object in a category
+	 * Check for the presence of a given object in the current category
 	 *
 	 * @param   string $type      		Type of category ('customer', 'supplier', 'contact', 'product', 'member')
 	 * @param   int    $object_id 		Id of the object to search
@@ -1059,7 +1060,7 @@ class Categorie extends CommonObject
 	}
 
 	/**
-	 * Return the list of categories of an element id.
+	 * Return the list of the categories of a given element (a product, a customer, ...).
 	 * Warning, this load/fetch all qualified categories.
 	 *
 	 * @param	int		$id			Id of element
@@ -1449,7 +1450,7 @@ class Categorie extends CommonObject
 
 	// phpcs:disable PEAR.NamingConventions.ValidFunctionName.ScopeNotCamelCaps
 	/**
-	 *	Returns the top level categories (which are not child)
+	 *	Returns the first level categories (which are not child)
 	 *
 	 *	@param	?int		$type		Type of category (0, 1, ...)
 	 *	@return	array<int,Categorie>|int<-1,-1>	Table of Object Category, -1 on error
@@ -1632,13 +1633,13 @@ class Categorie extends CommonObject
 	}
 
 	/**
-	 * Return list of categories (object instances or labels) linked to element of id $id and type $type
-	 * Should be named getListOfCategForObject
+	 * Return list of categories (object instances or labels) linked to a given object having id $id and type $type.
+	 * Should be named getListOfCategForObject.
+	 * Try to use it only with parameter $mode = 'id' or 'label'.
 	 *
 	 * @param   int    		$id                 Id of element
 	 * @param   string|int	$type               Type of category ('customer', 'supplier', 'contact', 'product', 'member') or (0, 1, 2, ...)
-	 * @param   string 		$mode               'id'=Get array of category ids, 'object'=Get array of fetched category instances, 'label'=Get array of category
-	 *                                          labels, 'id'= Get array of category IDs
+	 * @param   string 		$mode               'id'=Get array of category IDs, 'label'=Get array of category labels, 'object'=Get array of fetched category instances
 	 * @return  Categorie[]|int[]|string[]|int  Array of category objects, labels or IDs or < 0 if KO
 	 */
 	public function containing($id, $type, $mode = 'object')