GotoSocial and Calckey both let you compose some formatting using Markdown, and one of the elements they allow are preformatted code blocks using this format:
```Line one does somethingThe next line does something elseand so on.```
They seem to encode it as
your code block, which makes sense, and they’re willing to read each others’ code blocks, though they didn’t accept the
...block that WordPress used, or the plain code block now that I think about it, which makes me wonder why I’m even running this test.
I guess the next step is going to be to see what this actually pushes out in ActivityPub.