diff --git a/htdocs/install/mysql/migration/13.0.0-14.0.0.sql b/htdocs/install/mysql/migration/13.0.0-14.0.0.sql
index b3d61af08f7..f12cd42e028 100644
--- a/htdocs/install/mysql/migration/13.0.0-14.0.0.sql
+++ b/htdocs/install/mysql/migration/13.0.0-14.0.0.sql
@@ -121,6 +121,6 @@ ALTER TABLE llx_societe ADD INDEX idx_societe_warehouse(fk_warehouse);
 
 ALTER TABLE llx_socpeople MODIFY poste varchar(255);
 
-ALTER TABLE llx_menu ADD COLUMN prefix varchar(255) NOT NULL AFTER titre;
+ALTER TABLE llx_menu ADD COLUMN prefix varchar(255) NULL AFTER titre;
 
 ALTER TABLE llx_chargesociales ADD COLUMN fk_user integer DEFAULT NULL;
diff --git a/htdocs/install/mysql/tables/llx_menu.sql b/htdocs/install/mysql/tables/llx_menu.sql
index 14c36e3a049..52b576411cb 100644
--- a/htdocs/install/mysql/tables/llx_menu.sql
+++ b/htdocs/install/mysql/tables/llx_menu.sql
@@ -36,7 +36,7 @@ CREATE TABLE llx_menu
 	url           varchar(255) NOT NULL,					-- Relative (or absolute) url to go
 	target        varchar(100) NULL,						-- Target of Url link
 	titre         varchar(255) NOT NULL,					-- Key for menu translation
-	prefix        varchar(255) NOT NULL,					-- prefix
+	prefix        varchar(255) NULL,					    -- prefix
 	langs         varchar(100),								-- Lang file to load for translation
 	level         smallint,									-- Deprecated. Not used.
 	perms         text,										-- Condition to show enabled or disabled