Oh
In the case of Scratchblocks, "they" is one person, Tim Radvan, who I'm pretty sure was still in secondary school at the time. He just wrote it and made a pull request. And he designed it to support Snap! notations not in Scratch itself, such as grey rings (he's English) and custom C-shaped blocks.
Sadly, Tim is now out of university and has both a job and a family, so he no longer has an infinite amount of free time. So if this is going to happen on the Snap! forum, one of you lot is going to do it! But honestly I find it faster to make a script pic than to write up Scratchblocks notation.
There is a post with a link to the Discourse component.
With SVG mod, "Script pic..." is even more useful but it must be built as a SNAP library or project.
Oops, I apologize for forgetting that. I'll hereby ask @bromagosa to take a look at installing it, in his copious free time. (<-- sarcasm)
Hmm... is that an actual Discourse plugin? Unzipping it in plugins/ didn't seem to do anything at all.
@dardoro, maybe you can illuminate me?
It can be installed by UI as a "Component" from filesystem or URL.
Can be copied also as custom header.
Plugin source
This code replaces "[scratchblocks]" tag as shown in this thread
Help With Developing a Discourse Plugin for modified scratchblocks ‘snap-blocks’
Disclaimer as in above thread: "Maybe You find it useful - there is a proof of concept of such module..."
I see, I thought it was a plugin, thanks! 
[scratchblocks]
seems to have worked
[/scratchblocks]
For anyone else - I had to refresh my browser to see the update
[scratchblocks]
say (join (bromagosa) [Can we have a button that automatically adds the scratchblocks tags?])
[/scratchblocks]
[scratchblocks]
tell [ snapenilk ] to <(ask [cycomachead]::control) :: grey ring> ::control
[/scratchblocks]
@cycomachead is the forum hacker
Is there a place where I could go to find out which staff members are experts for which parts of Snap! (e.g. Jens wrote Morphic and knows about the back-end)?
the problem is that images like @addInput, @delInput, and others don't load, oh, and I found out you have to put the html tags
<p dir="ltr">...</p>around the scratchblocks tags in order to not get
[scratchblocks]@addInput[/scratchblocks].
(also, @addInput and @deInput are important with snapblocks)
Jens is the primary authority on Snap! itself. Michael is the primary expert on the forum. Bernat is the primary expert on the web site. All of them have dealt with the cloud back end, but if I had a question I'd start with Michael I think. Joan has been contributing mainly to Snap! itself. Jadga has mostly contributed to the SAP MOOC development. As for me, I'm a dilettante, but a lot of the user interface design for things like gray rings, the make a block dialog, the long form input dialog, etc., are my doing. And I'm the one who knows about languages other than Smalltalk, such as Scheme, Object Logo, and APL, all of which have contributed major design elements to Snap!. (Design elements from Smalltalk are Jens's work.)
P.S. I hope I'm going to see blocks in a color other than red...
[scratchblocks]
say( join [Updated on Github to v] [3.5] )
reinstall required
[/scratchblocks]
There are restrictions for using SVG on the forum. The output of the scratchblocks can be garbled by HTML filtering or some sort of post-processing.
Thank you; I have bookmarked this for future reference.
EDIT: Yet, for some reason, every time I click on the bookmark, it goes to a much later reply in this topic.
I have no experience with Scratchblocks @tjvr set them up before the forum was public.
If someone works on a better plugin I can help install it, but I don't really have the time to contribute to the main development.
There is no need for two adapters doing the same thing. It's better to stick to Tim's module, as my code is only draft of Discourse adapter/wrapper to @tjvr lib.