Pipeline rule, multiple values using regex function, only possible to return value ["0"]

Graylog Central (peer support)
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2

As @tmacgbay mentioned in this other post, Pipeline rule to generate a Object field with obtained IPs (multi_value) for a QNAME, from a DNS LookUp Table, I use the debug() function to review the content of of the field
multiIPs_extract[“1”]
And again, like the other post, it’s empty, even should have content based on the example:

[root@neoappliance ~]# tail -f /var/log/graylog-server/server.log | grep "Dropped message from"
2020-04-13T15:04:09.505-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from 
2020-04-13T15:04:09.505-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from 
2020-04-13T15:04:09.505-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from 
2020-04-13T15:04:09.506-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from 
2020-04-13T15:04:10.467-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from 
2020-04-13T15:04:10.468-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from 
2020-04-13T15:04:10.468-03:00 INFO  [Function] PIPELINE DEBUG: Dropped message from

So I’m think maybe there is a bug here, but I don’t know enough of Graylog to guarantee this.

Maybe any Devoloper of Graylog can take a look to this post and answer this last question.

Thanks in advance for all your help.

Regards,
Alejandro