DEVONthink uses MultiMarkdown 6.x which doesn’t support this (yet). As far as I known this is a Markdown extension introduced by github and one of Markdown’s shortcomings is indeed that there’s no official specification.
I get the sense that in the long-term CommonMark will emerge as the standard - any chance of supporting that?
Among other reasons, you have noted the popularity of Discourse as evidenced by this Forum. Discourse has been a strong force in advancing the use of Markdown - and they clearly support the CommonMark standard.
I get the sense that in the long-term CommonMark will emerge as the standard…
I would not get this sense from everything I’m reading. There are plenty of Markdown flavors and MultiMarkdown is really seen as the successor to Gruber’s original work.
Slack style emoji isn’t a Markdown convention. DEVONthink on the Mac has support specifically for it. However, Markdown documents support unicode characters so you can add emoji with the emoji keyboard or Character palette.
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