Change `fences` default to `true`

[wooorm]

Initial checklist

• I read the support docs
• I read the contributing guide
• I agree to follow the code of conduct
• I searched issues and couldn’t find anything (or linked relevant results below)

Problem

Fenced code is (arguably) much better than indented code.

• Indented code and lists interfere
• Indented code does not work in MDX
• Indented code uses 4 spaces, block quotes use a > and one space, lists use different “indents”, making markup source code impossible to align, so best to not even try
• fenced code supports language flags, which are super useful
• fenced code supports “meta” (arbitrary stuff), which is while not used much, useful in plugins

Historically fenced code was not supported everywhere. I think we’re now at a point where it’s basically everywhere. Hence this suggestion.

Solution

default to fences: true.

Alternatives

as is

[Murderlon]

Definitely agree with this one.

[github-actions]

Hi! This was closed. Team: If this was fixed, please add phase/solved. Otherwise, please add one of the no/* labels.