Steps to reproduce issue

1. Go to Site administration > Advanced features, turn off Use tags and click Save changes.
2. Create a course.
3. From the course page select Question bank from the More⌄ menu.

Expected results

The question bank page loads without error.

Actual results

Exception - qbank_tagquestion\plugin_feature::get_question_filters(): Return value must be of type array, none returned

More information about this error
Debug info:
Error code: generalexceptionmessage
Stack trace:

    line 44 of /question/bank/tagquestion/classes/plugin_feature.php: TypeError thrown
    line 1559 of /question/classes/local/bank/view.php: call to qbank_tagquestion\plugin_feature->get_question_filters()
    line 927 of /question/classes/local/bank/view.php: call to core_question\local\bank\view->add_standard_search_conditions()
    line 910 of /question/classes/local/bank/view.php: call to core_question\local\bank\view->wanted_filters()
    line 65 of /question/edit.php: call to core_question\local\bank\view->display()