Slack 'Attachment' Images not displaying

[werkkrew]

I have a slack-compatible payload as detailed below:

{
	"username":"PlexBot",
	"text":"Plex (Foo)\r\nAmerican Dharma was recently added to Plex.",
	"attachments":
	[{
		"title":"American Dharma (2019)",
		"text":"A portrait of controversial Breitbart honcho and Donald Trump advisor, Stephen K. Bannon.",
		"title_link":"https://www.imdb.com/title/tt8804284",
		"fields":
		[{
			"short":true,
			"value":"<https://www.imdb.com/title/tt8804284|IMDb>",
			"title":"View Details"
		}],
		"fallback":"Image for American Dharma (2019)",
		"thumb_url":"https://i.imgur.com/HzH2885.jpg"
	}],
	"icon_url":"https://i.imgur.com/iF8m9LE.png"
}

In Riot, this payload displays as:

I am not sure if the 'thumb_url" and/or 'icon_url' parameters are implemented as per #17 but was asked to open an issue anyway.

[Just-Insane]

Did you ever find a solution to this?

I'm thinking it would be possible to build a go template that takes this JSON and sends it out to matrix formatted nicely, but I'm having trouble figuring out how to write the template.