Callback before_http_headers in format_onetopic component should be migrated to new hook callback for core\hook\output\before_http_headers
- line 7246 of /lib/moodlelib.php: call to debugging()
- line 7310 of /lib/moodlelib.php: call to {closure}()
- line 47 of /lib/classes/hook/output/before_http_headers.php: call to get_plugins_with_function()
- line 858 of /lib/classes/output/core_renderer.php: call to core\hook\output\before_http_headers->process_legacy_callbacks()
- line 120 of /index.php: call to core\output\core_renderer->header()