J'ai trouvé d'où venait le problème :
modification à faire dans un fichier du thème clean, classes > core_renderer/php
code à mettre en commentaire (version 2.9.2) :
public function context_header($headerinfo = null, $headinglevel = 1) {
if ($this->should_render_logo($headinglevel)) {
return html_writer::tag('div', '', array('class' => 'logo'));
}
return parent::context_header($headerinfo, $headinglevel);
}
/**
* Determines if we should render the logo.
*
* @param int $headinglevel What level the 'h' tag will be.
* @return bool Should the logo be rendered.
*/
protected function should_render_logo($headinglevel = 1) {
global $PAGE;
// Only render the logo if we're on the front page or login page
// and the theme has a logo.
if ($headinglevel == 1 && !empty($this->page->theme->settings->logo)) {
if ($PAGE->pagelayout == 'frontpage' || $PAGE->pagelayout == 'login') {
return true;
}
}
return false;
}
à remplacer par la version 2.9.1 :
public function context_header($headerinfo = null, $headinglevel = 1) {
if ($headinglevel == 1 && !empty($this->page->theme->settings->logo)) {
return html_writer::tag('div', '', array('class' => 'logo'));
}
return parent::context_header($headerinfo, $headinglevel);
}