In the documentation for log_slow_filter
https://mariadb.com/kb/en/server-system-variables/#log_slow_filter

It says that the default value is:

admin, filesort, filesort_on_disk, filesort_priority_queue, full_join, full_scan, query_cache, query_cache_miss, tmp_table, tmp_table_on_disk

However, if we paste this exactly into the config, the config checks fails for:

Error while setting value 'admin, filesort, filesort_on_disk, filesort_priority_queue, full_join, full_scan, query_cache, query_cache_miss, tmp_table, tmp_table_on_disk, not_using_index' to 'log_slow_filter'

The correct way is to list these without spaces after the commas.

It might be worth either removing the spaces in the documentation, or have a line/warning mentioning that the options must be set without spaces.