Documentation search error after update to 2.11

I have Ubuntu 20.04 and using the latest icinga2 and icingaweb2. I noticed today that when I search something, I get this error below. I can live without it by disabling the DOC module but will be good to find the fix for this.

Uncaught TypeError: Return value of Icinga\Module\Doc\Search\DocSearchIterator::accept() must be of the type bool, object returned in /usr/share/icingaweb2/modules/doc/library/Doc/Search/DocSearchIterator.php:64
Stack trace:
#0 [internal function]: Icinga\Module\Doc\Search\DocSearchIterator->accept()
#1 /usr/share/icingaweb2/modules/doc/library/Doc/Search/DocSearchIterator.php(96): FilterIterator->rewind()
#2 /usr/share/icingaweb2/modules/doc/application/views/scripts/search/index.phtml(4): Icinga\Module\Doc\Search\DocSearchIterator->isEmpty()
#3 /usr/share/php/Icinga/Web/View.php(235): include(‘/usr/share/icin…’)
#4 /usr/share/icingaweb2/library/vendor/Zend/View/Abstract.php(877): Icinga\Web\View->_run()
#5 /usr/share/icingaweb2/library/vendor/Zend/Controller/Action/Helper/ViewRenderer.php(904): Zend_View_Abstract->render()
#6 /usr/share/icingaweb2/library/vendor/Zend/Controller/Action/Helper/ViewRenderer.php(925): Zend_Controller_Action_Helper_ViewRenderer->renderScript()
#7 /usr/share/icingaweb2/library/

#0 [internal function]: Icinga\Application\Web->Icinga\Application{closure}()
#1 {main}