This page should be using theme lambda which cannot be initialised. Nor can the site theme lambda. Falling back to boost

• line 725 of /lib/outputlib.php: call to debugging()
• line 1739 of /lib/pagelib.php: call to theme_config::load()
• line 756 of /lib/pagelib.php: call to moodle_page->initialise_theme_and_output()
• line 1011 of /lib/pagelib.php: call to moodle_page->magic_get_theme()
• line 108 of /index.php: call to moodle_page->get_renderer()