Not getting thumbnails of images in attachments through automations (Slack/email)

Hmm, for Slack, if you're using automations alone, I think the best you can hope for might be the link preview I'm afraid, and I achieved this by sending the Expiring Attachment URL:

If you use the Slack API I think maybe you could add it as an attachment to the message, but I don't think you would be able to get the image to appear in the middle of your message.  (Actually, if you could teach me how to do this in the Slack client I'd be super interested to learn that too; I just tried to do this on Slack and all my image attachments just showed up at the bottom of the message)

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For emails, if you want the images to show up in the email itself (i.e. not as attachments to the email), I'm afraid you'll need to host them somewhere and then use those hosted images in your email instead

@Lucas_Vos You can do this with Make's Slack automations. You can add media to the "Create a Message" module. As Adam said, they will likely show up as attachments, but you will be able to see previews of them.