Changes to the print_header API and use of $PAGE are breaking the questionnaire module. Viewing a questionnaire gives the error:

This page did no call $PAGE->set_url(...). Relaying on a guess.

• line 338 of /lib/pagelib.php: call to debugging()
• line 450 of /lib/pagelib.php: call to moodle_page->get_url()
• line 1364 of /lib/blocklib.php: call to moodle_page->__get()
• line 857 of /lib/blocklib.php: call to block_add_block_ui()
• line 312 of /lib/blocklib.php: call to block_manager->ensure_content_created()
• line 833 of /lib/outputrenderers.php: call to block_manager->region_has_content()
• line 707 of /lib/outputrenderers.php: call to moodle_core_renderer->handle_legacy_theme()
• line 1879 of /lib/outputrenderers.php: call to moodle_core_renderer->header()
• line 185 of /lib/setuplib.php: call to moodle_core_renderer->fatal_error()
• line ? of unknownfile: call to default_exception_handler()

...and...

Coding error detected, it must be fixed by a programmer: The $meta parameter to print_header is no longer supported. You should be able to do everything you want with $PAGE->requires and other such mechanisms.