I just ran a test with https://www.spamhaus.org/drop/drop.txt and it seems to work fineYou can check the alias under firewall/diagnostics/aliases
For long-term users of the DROP files in text format, we recommend you update your configuration with the above JSON files as soon as your cycles allow. If you require continued long-term use of a text file, the jq command can always be used to convert the JSON.N.B. The text files are still being populated however, in time, these will be deprecated; users will be notified with ample notice before deprecation takes place.