Issue: Call to undefined method vw_Version_Model_XF::template_version()

I got this error when testing upgrade to 4.0.23b on my staging server:

Error: Call to undefined method vw_Version_Model_XF::template_version() - vault/core/view/stylevar/vw.php:39
Generated By: alfa, A moment ago

Stack Trace
#0 /vault/core/view/stylevar/xf.php(62): vw_StyleVar_View->ready()
#1 /vault/core/view/template/xf.php(47): vw_StyleVar_View_XF->ready()
#2 /vault/core/view/template/xf.php(102): vw_Template_View_XF->_construct_delayed()
#3 /vault/core/model/vw.php(717): vw_Template_View_XF->ready()
#4 /vault/core/view/cp/xf.php(40): vw_Hard_Core::fetch_template('page_container_...', 'Admin')
#5 /vault/core/view/cp/xf.php(402): vw_CP_View_XF->print_script_output()
#6 /vault/core/controller/cp/vw.php(339): vw_CP_View_XF->response()
#7 /library/vw/XenForo/ControllerAdmin/Wiki.php(129): vw_CP_Controller->response()
#8 /library/vw/XenForo/ControllerAdmin/Wiki.php(182): vw_XenForo_ControllerAdmin_Wiki->actionIndex()
#9 /library/XenForo/FrontController.php(369): vw_XenForo_ControllerAdmin_Wiki->actionUpgrade()
#10 /library/XenForo/FrontController.php(152): XenForo_FrontController->dispatch(Object(XenForo_RouteMatch))
#11 /admin.php(13): XenForo_FrontController->run()
#12 {main}
Request State
array(3) {
["url"] => string(60) "/admin.php?wiki/upgrade"
["_GET"] => array(1) {
["wiki/upgrade"] => string(0) ""
}
["_POST"] => array(0) {
}
}

xf 1.5.21
php 7.2.5