Send CSV to Slack using ChatOps

I am trying to send output of one step of workflow as a CSV attachment to Slack but I guess when I looked at the following

What is the correct input for the attachment in the Slack plugin?

it turns out CSV cannot be sent as attachments to Slack messages. Is this still the case?

Correct. “Attachment” in Slack, unfortunately, doesn’t mean “Attachment” as normal people think of it.

I thought we had fixed that in the documentation, but I guess it’s still on the roadmap.