qa_register_plugin_module() can only be called from a plugin qa-plugin.php file

Stack trace:

require() in index.php:13
require() in qa-index.php:189
qa_get_request_content() in qa-page.php:47
require() in page.php:195
qa_load_modules_with() in default.php:100
qa_load_module() in qa-base.php:974
require_once() in qa-base.php:920
qa_register_plugin_module() in qa-widget-anywhere.php:24