diff --git a/htdocs/main.inc.php b/htdocs/main.inc.php
index b0b0cccf85a69fb8d507d8a2cc44709a06733e97..99196fed25ada934a61a687d3082c4514a238481 100644
--- a/htdocs/main.inc.php
+++ b/htdocs/main.inc.php
@@ -876,7 +876,7 @@ function top_htmlhead($head, $title='', $disablejs=0, $disablehead=0, $arrayofjs
         print '<!-- Includes for Dolibarr, modules or specific pages-->'."\n";
         // Output style sheets (optioncss='print' or '')
         $themepath=dol_buildpath((empty($conf->global->MAIN_FORCETHEMEDIR)?'':$conf->global->MAIN_FORCETHEMEDIR).$conf->css,1);
-        $themeparam='?lang='.$langs->defaultlang.'&amp;theme='.$conf->theme.(GETPOST('optioncss')?'&amp;optioncss='.GETPOST('optioncss','alpha',1):'').'&amp;userid='.$user->id;
+        $themeparam='?lang='.$langs->defaultlang.'&amp;theme='.$conf->theme.(GETPOST('optioncss')?'&amp;optioncss='.GETPOST('optioncss','alpha',1):'').'&amp;userid='.$user->id.'&amp;entity='.$conf->entity;
         if (! empty($_SESSION['dol_resetcache'])) $themeparam.='&amp;dol_resetcache='.$_SESSION['dol_resetcache'];
         //print 'themepath='.$themepath.' themeparam='.$themeparam;exit;
         print '<link rel="stylesheet" type="text/css" title="default" href="'.$themepath.$themeparam.'">'."\n";