Also, Markdown doesn't support ``` fenced code blocks; that's a common misconception. I don't know which Markdown derivative originated them (maybe GFM?) but they ended up in CommonMark.
There isn't a single markdown. There are many different flavors, and all of them are markdown. Many include ``` (GitHub, Kdoc, pandoc, reddit, commonmark), especially as it allows you to specify the language if you want. I actually don't know if any tool I use that doesn't support them.