I have an error since the last update (3.9.0)

WARNING: /INSTALL_DIR/core/Plugin/Manager.php(451): Warning - is_dir(): open_basedir restriction in effect. File(/INSTALL_DIRplugins/Annotations) is not within the allowed path(s): (/INSTALL_DIR/) - Matomo 3.9.0 - Please report this message in the Matomo forums: https://forum.matomo.org (please do a search first as it might have been reported already)

Because there's a mistake in the path : /INSTALL_DIRplugins/Annotations (it's missing one /)

$corePluginsDir = PIWIK_INCLUDE_PATH . 'plugins/' . $pluginName;
should perhaps be replaced by:
$corePluginsDir = PIWIK_INCLUDE_PATH . '/plugins/' . $pluginName;

Thank you for your work / Merci beaucoup

Anthony