chore(showCode): Support old syntax too

[PLNech]

Should solve #294 (but please review the code, my JS might be rusted 😁)

[PLNech]

Hmm not sure why we see lots of changes in the GitHub UI, is it right? I used github.dev to fork and do that change only so I doubt I changed formatting or trailing spaces?

The only intended change is this:

Edit: once I hide whitespace in GitHub UI, I see only the expected change 😌